References in here are just guidance, they can be not used in the future.
- https://www.tutorialspoint.com/cplusplus/cpp_object_oriented.htm
- https://www3.ntu.edu.sg/home/ehchua/programming/cpp/cp3_OOP.html
- https://www.tutorialspoint.com/cplusplus/cpp_exceptions_handling.htm
- https://en.cppreference.com/w/cpp/language/operators
- https://en.cppreference.com/w/cpp/language/friend
- https://docs.oracle.com/javase/tutorial/java/concepts/
- https://www.javatpoint.com/java-oops-concepts
- https://developer.mozilla.org/en-US/docs/Learn/JavaScript/Objects/Object-oriented_JS
- https://javascript.info/object-oriented-programming
- https://www.sitepoint.com/object-oriented-javascript-deep-dive-es6-classes/
- https://kamranahmed.info/blog/2015/01/03/private-and-public-scopes-in-javascript/
- https://www.lua.org/pil/16.html
- http://lua-users.org/wiki/ObjectOrientationTutorial
- http://lua-users.org/wiki/ObjectOrientedProgramming
- https://www.lua.org/pil/8.4.html
- http://lua-users.org/wiki/MetamethodsTutorial
- http://www.perltutorial.org/perl-oop/
- https://perldoc.perl.org/perlootut.html
- http://ods.com.ua/win/eng/program/Perl5Unleashed/ch5.phtml
- https://www.perl.com/pub/2002/11/14/exception.html/
- https://www.perlmonks.org/?node_id=571509
- https://www.perlmonks.org/?node_id=8251
- http://php.net/manual/en/language.oop5.php
- https://www.tutorialspoint.com/php/php_object_oriented.htm
- https://docs.python.org/3/tutorial/classes.html
- http://www.tutorialspoint.com/python/python_classes_objects.htm
- https://docs.python.org/3/tutorial/errors.html
- https://rszalski.github.io/magicmethods/
- https://www.python-course.eu/python3_magic_methods.php
- https://ruby-doc.org/docs/ruby-doc-bundle/UsersGuide/rg/oothinking.html
- https://www.tutorialspoint.com/ruby/ruby_object_oriented.htm
- http://www.poodr.com
- https://www.tutorialspoint.com/ruby/ruby_exceptions.htm
- https://ruby-doc.org/core-2.1.1/Object.html
- https://en.wikipedia.org/wiki/Comparison_of_programming_languages_by_type_system
- http://www.jvoegele.com/software/langcomp.html
- https://en.wikipedia.org/wiki/Comparison_of_programming_languages_(object-oriented_programming)
- https://www.cs.drexel.edu/~introcs/Fa15/notes/06.1_OOP/titleslide.html?CurrentSlide=0
- http://web.eecs.utk.edu/~huangj/CS302S04/notes/oo-intro.html
- https://www.yegor256.com/2016/08/15/what-is-wrong-object-oriented-programming.html
- https://medium.com/@cscalfani/goodbye-object-oriented-programming-a59cda4c0e53
- https://medium.com/@agent47darksoul/lets-talk-about-object-oriented-programming-d9f1602ebaa7
- https://en.wikiquote.org/wiki/Object-orientation
- http://web.cecs.pdx.edu/~black/publications/O-JDahl.pdf
- http://www.exforsys.com/tutorials/oops-concepts/the-history-of-object-oriented-programming.html
- http://wiki.c2.com/?AlanKaysDefinitionOfObjectOriented
- https://www.webopedia.com/TERM/P/polymorphism.html
- https://en.wikipedia.org/wiki/Tcl
- https://en.wikipedia.org/wiki/Smalltalk
- https://en.wikipedia.org/wiki/Vala_(programming_language)
- https://en.wikipedia.org/wiki/Apache_Groovy
- https://en.wikipedia.org/wiki/Go_(programming_language)
- https://en.wikipedia.org/wiki/D_(programming_language)#Object-oriented
- https://en.wikipedia.org/wiki/Dart_(programming_language)
- https://en.wikipedia.org/wiki/Self_(programming_language)
- https://en.wikipedia.org/wiki/R_(programming_language)
- https://en.wikipedia.org/wiki/Scala_(programming_language)#Object-oriented_extensions
- https://en.wikipedia.org/wiki/Swift_(programming_language)#Comparisons_to_other_languages
- https://en.wikipedia.org/wiki/Kotlin_(programming_language)
- https://en.wikipedia.org/wiki/Racket_(programming_language)
- https://en.wikipedia.org/wiki/C_Sharp_(programming_language)