Below are some useful links for learning quantitative research methods.

• Harvard Math Prefresher for Political Scientists: https://iqss.github.io/prefresher/
• Quanteda Tutorials by Kohei Watanabe and Stefan Müller: https://tutorials.quanteda.io/
• Scrapy documentation: https://docs.scrapy.org/en/latest/
• LaTeX cheat sheet: https://wch.github.io/latexsheet/latexsheet.pdf
• R Markdown cheat sheet: https://rstudio.github.io/cheatsheets/rmarkdown.pdf
• Regular Expression cheat sheet: https://cheatography.com/davechild/cheat-sheets/regular-expressions/pdf/?last=1584011681