It seems to me as if many modern texts are rather streamlined. They are designed not to expect too much from the reader but they often miss the depth of respective classical literature.
The purpose of this record is to collect highly recommended classical texts. Quality and depth of the subject matter should serve as a benchmark. Suitability for beginners should be irrelevant.
For a text to be regarded classical it should have proven its value for one decade at least. Nevertheless, it should expose the present state of the art.
The final list will contain each recommended text with $10$ or more votes.
In order to make this work, please restrict yourself to one proposal per answer/comment.
Thank you for your contribution!
- Rudin - Principles of Mathematical Analysis, 3rd Edition, 1976
- Graham, Knuth, Patashnik - Concrete Mathematics, 2nd Edition, 1994
- Munkres - Topology, 2nd Edition, 2000