Ahrens How To Take Smart Notes Ahrens - How to Take Smart Notes Documents a personal knowledge management approach heavily based on Zettelkasten. See also site References Ahrens, Sönke. How to Take Smart Notes: One Simple Technique to Boost Writing, Learning and Thinking: For Students, Academics and Nonfiction Book Writers. North Charleston, SC: CreateSpace, 2017. Zotero, blog