https://en.wikibooks.org/wiki/Abstract_Algebra/Quaternions https://en.wikibooks.org/wiki/Abstract_Algebra/Quaternions or https://books.google.ie/books?id=ouvZKQ

https://en.wikibooks.org/wiki/Abstract_Algebra/Quaternions https://en.wikibooks.org/wiki/Abstract_Algebra/Quaternions or https://books.google.ie/books?id=ouvZKQiykf4C&pg=PA98&lpg=PA98&dq=quaternions https://books.google.ie/books?id=ouvZKQiykf4C&pg=PA98&lpg=PA... I am from Dublin, where quaternions were invented, so they get mentioned a lot by mathematicians and physicists here, maybe getting a higher billing than they do elsewhere. Computer graphics is obviously a place to go for introductions also, but it is typically going to be a more applied and less rigorous treatment.