In der Werbemail eines Literaturhändlers fiel mir dieses Buch auf:

A subject totally ignored by serious philatelist, the postal rates were different, Blindman's Mail, or How the Blind have been served by the Post by Garvin Fryer, Details of the correspondence between institutions for the blind and the Post Office 1894-1939, 42 tables of postage rates, details on the postal rates and regulations from 1898 to date. 2010, etc, 184 pages, full color, cloth, 2010, 165+12 pages, dedication page in Braille, cloth with dj, in color, limited stock, price, $65.00

Evtl. ist das ja von Interesse.