A complete reference book (115 pages) of the flags and coats of arms of the states of Germany of the second Reich.  This is a reprint but I have not found the original. Small book actually published under the moniker "pocketbook". Each state is covered first in a two page spread. On the first page is information on the crest and state to include area and population of the time.  Then the Wappen itself.   Many sources use this as the source for their information. Elsewhere in this site we have copied many of these wappen with permission from http://www.heraldique-europeenne.org

There is also a section of flags. This shorter section is also available electronically as has been used in our site with permission from FOTW Flags Of The World website at http://flagspot.net/flags  So I guess I am not enamored by buying this as it is all available on the net easily. Nice reference.