From GALAXYMAP.ORG:

The HII region Sh 2-261 is often called Lower's nebula because it appears on a photographic plate taken by the father-and-son team of Harold and Charles Lower in 1939.
The Lowers were amateur astronomers, accomplished telescope makers and pioneering astrophotographers from San Diego, California. Harold Lower published a pamphlet
in 1939 describing an 8 inch Schmidt camera that he and his son had constructed several years previously.
He notes that the camera has been especially useful in photographing what are now called HII regions