**Disclaimer:** I was really uncertain about posting this question, because it is quite similar to this https://mathoverflow.net/questions/18041/algebraic-topology-beyond-the-basics-any-texts-bridging-the-gap?answertab=active#tab-top. I don't know if it would be best to put my question as a comment on https://mathoverflow.net/questions/18041/algebraic-topology-beyond-the-basics-any-texts-bridging-the-gap?answertab=active#tab-top or rather create this new question. However, I thought that pheraps it brings to new interesting answers.

**Question:** I am a PhD student in algebraic topology, and I learned the basics of the subject from some of the many valuable texts suitable for a first course. Now, I am searching for more advanced books which I can keep as a reference for more advanced topics that I might encounter in the future. 

To be more precise: suppose we divide the literature on algebraic topology in the following categories:

 1. **Standard books** (e.g. the books by Hatcher, Tammo tom Dieck, Massey)
 2. **Non standard books**: those with a different approach to the subject and that contain some more advanced topics, for example *Algebraic topology from an homotopical point of view* by Aguilar, Gitler, Prieto (https://www.amazon.com/dp/1441930051) or, even if more advanced, *From categories to homotopy theory* by Richter (https://www.cambridge.org/core/books/from-categories-to-homotopy-theory/A109E2C4B720337DE19A15EB4FA8C9A6).
 3. **Advanced books**: they contain more advanced topics but they are not monographs, for example: *Differential forms in algebraic topology* by Bott and Tu (https://www.maths.ed.ac.uk/~v1ranick/papers/botttu.pdf),  
    *Homotopical topology* by Fomenko and Fuchs (https://link.springer.com/book/10.1007/978-3-319-23488-5), *A concise course in algebraic topology* by May (https://www.math.uchicago.edu/~may/CONCISE/ConciseRevised.pdf) or *Generalized cohomology* by Kono and Tamaki https://books.google.it/books/about/Generalized_Cohomology.html?id=3HY4ruJ6BigC&redir_esc=y)
 5. **Monographs**: those big books where you can find the details of a specific theory (e.g. *K-theory* by Atiyah, *Operads in Algebra, Topology and Physics* by Markl, Shnider, and Stasheff, *Rational Homotopy Theory* by Felix, Halperin, Thomas)

The books I am looking for are those in the second and third category. So, books that approach algebraic topology from an unusual point of view and/or contains a bunch of more advanced topics.

Other titles would be very welcome, as well as comments about the books I listed above.