https://ultimate-mushroom.com/inedible/384-rhodocollybia-maculata.html
Rhodocollybia maculata: The Ultimate Mushroom Guide
Rhodocollybia maculata: what you should know about the mushroom and identification with photos. Also, check all-around information about this mushroom.
the ultimaterhodocollybiamushroomguide
https://www.mykoweb.com/CAF/species/Rhodocollybia_butyracea.html
California Fungi: Rhodocollybia butyracea
Photographs and descriptions of the Mushrooms and other Fungi of California, USA
california fungirhodocollybia