dwinsemius
commented
4 years ago He later wrote the "R Book". I found several errors in the sections describing the language and it was for a time a persistent source of questions on the rhelp mailing list. It was of more use as a set of statistical programming examples than it was as a reliable guide to the S/R language. Dalgaard's book would be a better recommendation.
My experience is only with Statistical Computing: An Introduction to Data Analysis Using S-Plus, but it was the best introduction to the statistical computing period (despite the name, it worked with R quite well). However, that experience is a bit dated, and I can see now, that he wrote more books on the theme and some of them specifically about R. And yes, the price of the books is quite unnerving. Hopefully, your university has them in the library.