AFAIK, the first design for implementation of vtables was by Bjarne Stroustrup in his paper Multiple Inheritance for C++ in 1986/1987.

Pdf at https://www.google.com/goto?url=CAESawHuR6pN4SDa5tLkqrSuoaot... and reissue at https://www.researchgate.net/publication/2396782_Multiple_In...

I read this in one of the documentation books (still have it somewhere) which came with SCO Unix (don't recall the date). This book contained articles on C++ only and was an introduction to the language and compiler (since the language was very new). I also remember that it had an article on Template mechanism.

Next was Jan Gray from Microsoft's excellent 1994 article in MSDN titled C++: Under the Hood which explained class layouts/vtables/etc. It is still a excellent read today. Pdf at https://www.google.com/goto?url=CAESewHuR6pNy2XLp9fzgwckhWpg...

Finally of course you have Inside the C++ Object Model by Stanley Lippman explaining everything in detail.