Yes, it was introduced in 1967 as a successor to Simula 1 and the language was called Simula 67. It influenced subsequent OO languages like CLU, C++, Java, and

Yes, it was introduced in 1967 as a successor to Simula 1 and the language was called Simula 67. It influenced subsequent OO languages like CLU, C++, Java, and Smalltalk. Barbara Liskov lent me a book that described it in 1973 and recommended that I read about Simula 67 before starting to work on a small part of the the CLU compiler design. I believe the book was Structured Programming by Dijkstra, Hoare, and Dahl. It had a chapter by Dahl describing Simula 67.