Letters written to Wm. P. and Louise Eggleston Collins from various family members. The original letters are stored in the Boulder Public Library, Carnegie Branch for Local History.

Letters from Alura Collins, daughter of Lin Collins

Letters from Florence and Edith Snover

Letters from Emogene

Letter from Esther Hollister

Letters from May Collins Snover Edward Nicolai

Letter from Will Collins

Articles about William Penn Collins, Jr., which appeared in the Boulder Camera

An article on the house at 1504 Pine Street, Boulder, CO