The Superior & Seattle Railroad & Interchange Gazette is an open source resource by Mr. John Siekirk. I asked Mr. Siekirk about it and his description is:
It started as a newsletter for my layout the Superior & Seattle Railroad, then others joined in, hence the Interchanges - now it has become a E-Magazine for modelers. No money changes hands - just modeling techniques and inspiration.
This is volume 2, number 11, November 2023.