This section is dedicated to many detailed and cumbersome mathematical derivations and solutions to miscellaneous topics in cosmology, that I did. I cannot guarantee, these documents are error-free. So, you are more than welcome to spot on any logical mistake, mathematical ambiguity or typo in the text in the comments section. There are many good resources are also available on the web. I will try to link those for respective files. Remember, all the links below lead to PDF files in new window.