All you needed to know about MFCC
- See answers by Amir Poorjam on RG https://www.researchgate.net/post/Why_we_take_only_12-13_MFCC_coefficients_in_feature_extraction
- He has also given his lecture notes https://www.researchgate.net/profile/Amir-Hossein-Poorjam/post/Why_we_take_only_12-13_MFCC_coefficients_in_feature_extraction/attachment/5e29bb633843b093839ccbc1/AS%3A850528695238656%401579793251438/download/Mfccs.pdf . These are very good.
- Have a look at this thesis and read the portions you like https://ir.canterbury.ac.nz/handle/10092/7561