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\newblock On {Subtyping} and {Matching}.
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Abadi, M., Cardelli, L., Pierce, B.~C., and Plotkin, G.D.
\newblock Dynamic typing in a statically typed language.
\newblock Technical Report~47, Digital Equipment Corporation, Systems Research
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\bibitem[\protect\citeauthoryear{Abadi \bgroup \em et al.\egroup
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Abadi, M., Cardelli, L., Curien, P.-L., and L{\'e}vy, J.-J.
\newblock Explicit substitutions.
\newblock Technical Report~54, Digital Equipment Corporation, Systems Research
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\bibitem[\protect\citeauthoryear{Albano \bgroup \em et al.\egroup
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Albano, A., Bergamini, R., Ghelli, G., and Orsini, R.
\newblock An introduction to the database programming language {Fibonacci}.
\newblock FIDE Technical Report Series FIDE/92/64, FIDE Project Coordinator,
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\bibitem[\protect\citeauthoryear{Amadio and Cardelli}{1993}]{AmCa93}
Amadio, R.M. and Cardelli, L.
\newblock Subtyping recursive types.
\newblock {\em ACM Transactions on Programming Languages and Systems}, 15(4),
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\bibitem[\protect\citeauthoryear{Atkinson and Bunemann}{1987}]{AtBu86}
Atkinson, M.P. and Bunemann, P.
\newblock Types and persistence in database programming languages.
\newblock {\em ACM Computing Surveys}, 19(2), June 1987.

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Birell, A., Nelson, G., Owicki, S., and Wobber, E.
\newblock Network objects.
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\bibitem[\protect\citeauthoryear{Black and Hutchinson}{1990}]{BlHu90}
Black, Andrew~P. and Hutchinson, Norman~C.
\newblock Typechecking polymorphism in {Emerald}.
\newblock Technical Report TR 90-34, Dept. of Computer Science, University of
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\bibitem[\protect\citeauthoryear{Bobrow \bgroup \em et al.\egroup
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Bobrow, D.G., De~Michiel, L.G., Gabriel, R.P., Keene, S.E., Kiczales, G., and
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\newblock Common lisp object system specification.
\newblock {\em ACM SIGPLAN Notices}, 23, September 1988.

\bibitem[\protect\citeauthoryear{Bracha and Griswold}{1993}]{BrGr93}
Bracha, Gilad and Griswold, David.
\newblock {Strongtalk:} typechecking {Smalltalk} in a production environment.
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\bibitem[\protect\citeauthoryear{Briot and Cointe}{1989}]{Briot89}
Briot, J-P. and Cointe, P.
\newblock Programming with explicit metaclasses in {Smalltalk-80}.
\newblock In {\em Proceedings of the Object-Oriented Programming Systems,
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\bibitem[\protect\citeauthoryear{Brown \bgroup \em et al.\egroup }{1991}]{B*91}
Brown, A.L., Mainetto, G., Matthes, F., M{\"u}ller, R., and McNally, D.J.
\newblock An open system architecture for a persistent object store.
\newblock Persistent Programming Research Report CS/91/9, University of St.
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\bibitem[\protect\citeauthoryear{Bruce \bgroup \em et al.\egroup
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Bruce, K.B., Crabtree, J., Murtagh, T.P., Gent, Robert van, Dimock, Allyn, and
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\newblock Safe and decidable type checking in an object-oriented language.
\newblock In {\em Proceedings OOPSLA'93}, pages 29--46, October 1993.

\bibitem[\protect\citeauthoryear{Bruce \bgroup \em et al.\egroup
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Bruce, K.B., Schuett, A., and Gent, R. van.
\newblock {PolyTOIL:} a type-safe polymorphic object-oriented language.
\newblock In {\em Proceedings ECOOP'95}. Springer-Verlag, 1993.
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\bibitem[\protect\citeauthoryear{Bruce}{1993}]{Bruc93}
Bruce, K.B.
\newblock Safe type checking in a statically typed object-oriented language.
\newblock In {\em Proceedings of the Twentieth ACM Symposium on Principles of
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\bibitem[\protect\citeauthoryear{Canning \bgroup \em et al.\egroup
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Canning, P.S., Cook, W.R., Hill, W.L., and Olthoff, W.
\newblock F-bounded polymorphism for object-oriented programming.
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\bibitem[\protect\citeauthoryear{Cardelli and Longo}{1991}]{CaLo91}
Cardelli, L. and Longo, G.
\newblock A semantic basis for {Q}uest.
\newblock {\em Journal of Functional Programming}, 1(4):417--458, October 1991.

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Cardelli, L., Martini, S., Mitchell, J.C., and Scedrov, A.
\newblock An extension of system {F} with subtyping.
\newblock In Ito, T. and Meyer, A.R., editors, {\em Theoretical Aspects of
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\bibitem[\protect\citeauthoryear{Cardelli \bgroup \em et al.\egroup
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Cardelli, L., Matthes, F., and Abadi, M.
\newblock Extensible grammars for language specialization.
\newblock In Beeri, C., Ohori, A., and Shasha, D.E., editors, {\em Proceedings
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Cardelli, L.
\newblock The {Quest} language and system (tracking draft).
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Castagna, G.
\newblock Covariance and contravariance: conflict without a cause.
\newblock Technical Report liens-94-18, LIENS, October 1994.

\bibitem[\protect\citeauthoryear{Chambers and Leavens}{1994}]{ChLe94}
Chambers, Craig and Leavens, Gary~T.
\newblock Typechecking and modules for multi-methods.
\newblock In {\em Proceedings OOPSLA '94}, volume~29 of {\em ACM SIGPLAN
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\bibitem[\protect\citeauthoryear{Chambers and Ungar}{1991}]{ChUn91}
Chambers, C. and Ungar, D.
\newblock Making pure object-oriented languages practical.
\newblock In {\em Proceedings of the Object-Oriented Programming Systems,
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\bibitem[\protect\citeauthoryear{Chambers}{1993}]{Cham92}
Chambers, C.
\newblock Object-oriented multi-methods in {Cecil}.
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\bibitem[\protect\citeauthoryear{Cook \bgroup \em et al.\egroup }{1990}]{CHC90}
Cook, W.R., Hill, W.L., and Canning, P.S.
\newblock Inheritance is not subtyping.
\newblock In {\em Proceedings of the Seventeenth ACM Symposium on Principles of
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\bibitem[\protect\citeauthoryear{Danforth and Forman}{1994}]{DaFo94}
Danforth, S. and Forman, I.~R.
\newblock Reflections on metaclass programming in {SOM}.
\newblock In {\em Proceedings OOPSLA'94}, pages 440--452, October 1994.

\bibitem[\protect\citeauthoryear{Eifrig \bgroup \em et al.\egroup
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Eifrig, J., Smith, S., Trifonov, V., and Zwarico, A.
\newblock Application of {OOP} type theory: State, decidability, integration.
\newblock In {\em Proceedings OOPSLA'94}, pages 16--30, October 1994.

\bibitem[\protect\citeauthoryear{Ellis and Stroustrup}{1990}]{ElSt90}
Ellis, M.A. and Stroustrup, B.
\newblock {\em The Annotated C++ Reference Manual}.
\newblock Addison-Wesley Publishing Company, 1990.

\bibitem[\protect\citeauthoryear{Ferber}{1989}]{Ferb89}
Ferber, J.
\newblock Computational reflection in class based object oriented languages.
\newblock In {\em Proceedings of the Object-Oriented Programming Systems,
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\bibitem[\protect\citeauthoryear{Gawecki and Matthes}{1994}]{GaMa94}
Gawecki, A. and Matthes, F.
\newblock The {Tycoon} {Machine} {Language} {TML} - an optimizable persistent
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\newblock FIDE Technical Report FIDE/94/100, Fachbereich Informatik,
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\bibitem[\protect\citeauthoryear{Gawecki and Matthes}{1995}]{GaMa95}
Gawecki, A. and Matthes, F.
\newblock Integrating query and program optimization using persistent {CPS}
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\newblock (submitted for publication), March 1995.

\bibitem[\protect\citeauthoryear{Gawecki \bgroup \em et al.\egroup
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Gawecki, A., Matthes, F., and Schmidt, J.W.
\newblock Definition of the {Tycoon} object-oriented {Language} {TooL}.
\newblock (In preparation), May 1995.

\bibitem[\protect\citeauthoryear{Gawecki}{1992}]{Gawe91a}
Gawecki, A.
\newblock An optimizing compiler for {Smalltalk}.
\newblock Bericht FBI-HH-B-152/92, Fachbereich Informatik, Universit\"at
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\newblock In German.

\bibitem[\protect\citeauthoryear{Ghelli}{1991}]{Ghel91}
Ghelli, G.
\newblock A static type system for message passing.
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\bibitem[\protect\citeauthoryear{Goguen}{1990}]{Gogu90}
Goguen, J.A.
\newblock Higher-order functions considered unnecessary for higher-order
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\newblock In Turner, D., editor, {\em Research Topics in Functional
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\bibitem[\protect\citeauthoryear{Goldberg and Robson}{1983}]{GoRo83}
Goldberg, Adele and Robson, David.
\newblock {\em Smalltalk 80: the Language and its Implementation}.
\newblock Addison-Wesley, May 1983.

\bibitem[\protect\citeauthoryear{Hewitt}{1987}]{Hewi77}
Hewitt, C.
\newblock Viewing control structures as patterns of passing messages.
\newblock {\em Artificial Intelligence}, (8):323--364, 1987.

\bibitem[\protect\citeauthoryear{{H\"olzle}}{1994}]{Hoel94}
{H\"olzle}, U.
\newblock {\em Adaptive Optimization for {Self}: Reconciling high performance
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\newblock PhD thesis, Stanford University, August 1994.

\bibitem[\protect\citeauthoryear{Hutchinson}{1987}]{Hutc87}
Hutchinson, Norman~C.
\newblock {\em {Emerald}: An Object-Based Language for Distributed
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\newblock PhD thesis, University of Washington, September 1987.

\bibitem[\protect\citeauthoryear{Johnson and Foote}{1988}]{John88}
Johnson, Ralph~E. and Foote, Brian.
\newblock Designing reusable classes.
\newblock {\em Journal of Object-Oriented Programming}, 1(2), 1988.

\bibitem[\protect\citeauthoryear{Kiczales \bgroup \em et al.\egroup
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Kiczales, G., Rivieres, J., and Bobrow, D.G.
\newblock {\em The Art of the Metaobject Protocol}.
\newblock MIT Press, 1991.

\bibitem[\protect\citeauthoryear{Lamb \bgroup \em et al.\egroup
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Lamb, C., Landis, G., Orenstein, J., and Weinreb, D.
\newblock The {ObjectStore} database system.
\newblock {\em Communications of the ACM}, 34(10):50--64, 1992.

\bibitem[\protect\citeauthoryear{Lamping}{1993}]{Lamp93}
Lamping, John.
\newblock Typing the specialization interface.
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\bibitem[\protect\citeauthoryear{Mathiske \bgroup \em et al.\egroup
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Mathiske, B., Matthes, F., and Schmidt, J.W.
\newblock On migrating threads.
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\bibitem[\protect\citeauthoryear{Matthes and Schmidt}{1991}]{MaSc91b}
Matthes, F. and Schmidt, J.W.
\newblock Bulk types: Built-in or add-on?
\newblock In {\em Proceedings of the Third International Workshop on Database
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\bibitem[\protect\citeauthoryear{Matthes and Schmidt}{1992}]{MaSc92a}
Matthes, F. and Schmidt, J.W.
\newblock Definition of the {Tycoon} {Language} {TL} -- a preliminary report.
\newblock Informatik Fachbericht {FBI-HH-B-160/92}, Fachbereich Informatik,
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\bibitem[\protect\citeauthoryear{Matthes and Schmidt}{1993}]{MaSc93b}
Matthes, F. and Schmidt, J.W.
\newblock System construction in the {Tycoon} environment: Architectures,
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\newblock In Spies, P.P., editor, {\em Proceedings of Euro-Arch'93 Congress},
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\bibitem[\protect\citeauthoryear{Matthes and Schmidt}{1994}]{MaSc94}
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\newblock Persistent threads.
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\bibitem[\protect\citeauthoryear{Matthes \bgroup \em et al.\egroup
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Matthes, F., M{\"u}ller, R., and Schmidt, J.W.
\newblock Object stores as servers in persistent programming environments --
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\newblock FIDE Technical Report Series FIDE/92/48, FIDE Project Coordinator,
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Matthes, F., M{\"u}{\ss}ig, S., and Schmidt, J.W.
\newblock Persistent polymorphic programming in {Tycoon}: An introduction.
\newblock FIDE Technical Report FIDE/94/106, Fachbereich Informatik,
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\bibitem[\protect\citeauthoryear{Matthes}{1993}]{Matt93}
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\newblock {\em Persistente Objektsysteme: Integrierte Datenbankentwicklung und
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\newblock Springer-Verlag, 1993.
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\bibitem[\protect\citeauthoryear{Meyer}{1988}]{Meye88}
Meyer, B.
\newblock {\em Object-oriented Software Construction}.
\newblock International Series in Computer Science. Prentice Hall, Englewood
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\bibitem[\protect\citeauthoryear{Meyer}{1989}]{Mey89}
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\newblock Static typing for {Eiffel}.
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\bibitem[\protect\citeauthoryear{Milner \bgroup \em et al.\egroup
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Milner, R., Tofte, M., and Harper, R.
\newblock {\em The Definition of {Standard ML}}.
\newblock MIT Press, Cambridge, Massachusetts, 1990.

\bibitem[\protect\citeauthoryear{Pierce and Turner}{1993}]{PiTu93b}
Pierce, B.C. and Turner, D.N.
\newblock Statically typed friendly functions via partially abstract types.
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\bibitem[\protect\citeauthoryear{Pierce}{1992}]{Pier92}
Pierce, B.~C.
\newblock Bounded quantification is undecidable.
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\bibitem[\protect\citeauthoryear{Ungar and Smith}{1987}]{UnSm87}
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\newblock {Self}: The power of simplicity.
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