EDIT: I hit “post” while I was in the middle of drafting my response. Sorry about that.
For your first question about storing source material, here are some forum posts you may want to look at:
- Working with Zotero: Zotero -> zotfile -> mdnotes -> obsidian -> dataview Workflow.
- For clipping web pages into Obsidian: Obsidian Web Clipper Bookmarklet with full Markdown support for images, headings, and code blocks, Yet another Markdown Clipper (Firefox possibly Chrome), MarkDownload - Markdown Web Clipper
- Browser extension for making & extract highlights on a web page: Web Clipper/Highlighter and Kindle highlights/notes extraction Extension
I’m sure you will find a lot of different opinions on where to store source material. Personally, I use Zotero to store the actual file and, if I feel so inclined, I paste a Zotero URI in the note. This allows me to click a link in Obsidian to launch Zotero which highlights the source document for me. Since I use Zotero as a file manager, I can double click the file to open it.
For your second question about Zettelkasten, there was a post on this forum recently where someone asked for basic guidance: Please ! Like explain a primary school student.
Finally, given your profession, you may want to keep snippets of the context of the studies and summary findings (also see a similar article here) within your vault along side your other notes.