Thor:
Lou Lathrop was a fireman and engineer on the D&RGW narrow gauge working out of Gunnison. In the 1930s, he wrote a series of stories for Railroad Magazine. In the 50s, he wrote a book titled "Little Engines & Big Men" that contained many of those stories. In the 70s, he did a second book titled "Rio Grande Glory Days." Both books have been out of print for a long time. You can find someone selling one or the other now and then, but be prepared to pay $$$ for them. I have both, but would not sell mine.