The 1847 issue
A comprehensive article by Calvert Hahn
The
1851 3c issue
A comprehensive study The 1851 1c and 3c issues
Just unbelievable. A huge, huge study on these two stamps. The 1851 3c issue
Great guide to this issue, well laid out site The 1869 Pictorials
A comprehensive article on this issue by the great man himself, the recently departed Calvert Hahn The
1869 90c
A development
of this popular Lincoln.
The 1903 1c
A complete study
liberally sprinkled with quality images. The 1875 1c
The definitive site on the 1c Franklin issue. The site is working towards a pictorial description of every plate position.
The 1903 issue
An informative site that contains a brief overview of each of the values
and their uses. The Museum of Essays and Proofs
Gradually expanding site that had large clear images. Beautiful site
