John and Carol McDougald, A History and Guide to North American Glass Pintype Insulators, volume 1 ONLY, published in 1990. Volume 1 has history on insulator companies and suppliers. Volume 2 has pictures and listings of the insulators but I don't have that volume. $25 postpaid, check, money order or PayPal friends & family, Rick Soller, Com574@clcillinois.edu