Many Malayalam university departments (University of Calicut, Sree Sankaracharya University) keep clean digital archives for research. If you are a student, your library proxy might give you access to a government-funded digital library (like Sayahna or Malayalam E-books ).
If you find the historical context a bit heavy, try listening to a summary or audiobook mayyazhippuzhayude theerangalil pdf better
(Most Useful for Readers/Researchers)