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How to become a pure mathematician or statistician (2008)
a List of Undergraduate and Basic Graduate Textbooks and Lecture Notes - the blog
If you decided to attend a class, don't expect the professor can teach, it always happen, especially in higher level courses. Moreover, some Chinese press in mainland China published photocopied of English text with a relatively cheap price. Although I'm not into reading books online, I should remind you that MIT's open recourse, the Archimedeans and Wikibooks provide another great sources of materials.
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