G and L Postcards WB
Offers a catalog of postcards with an early 20th century Halloween theme, geared towards collectors and dealers.
Island Curio Authentic Hawaiian Postcards
Keith J. Steiner's book on postcards of Hawaii between 1900 and 1915. Also includes a catalog of Island cards.
Valentines Valentines Valentines
Katherine Kreider's three books on antique valentines.