There are quite a few studies on the link to early cannabis abuse and psychosis (I link to one of them). Just Google it if you're interested.

https://pubmed.ncbi.nlm.nih.gov/29557759/

"It is now incontrovertible that heavy cannabis use increases the risk of psychosis".

That was after one quick Google search.

My article is more like a personal essay rather than a scientific article, as there is so much existing data on this subject I didn't think it necessary to link to more than a few studies.