I am posting this as a new entry rather than editing the previous entry which was Uranometria, Struve 2668 and The Living Star Atlas. Do 5 is part of the Dolidze catalogue of clusters which frequent the area of Cygnus. This cluster in particular is an eye catcher, also it is the home of Struve 2668. Again, it's position is 20h 20.3m RA, +39 24" DEC
Sources: Uranometria 2000.0 Vol 1 2nd Edition, Tirion et al and Double Stars for Small Telescopes by Sissy Haas.