Walter Lammerts' 1945 essay "The Scientific Basis of Rose Breeding".
A Brief Primer on Breeding Miniatures, by Paul Barden.
Major C. C. Hurst's 1922 document, "Notes On The Origin of The Moss Rose" has been added to the History and Rose Breeding sections of the site.
Here is a reprint of a 1967 article by Ralph Moore on the genetics of Moss and Miniature roses.
The Rose Hybridizers Association Homepage has now got a website, which will undoubtedly become a great resource for amateur rose hybridizers.
Here is a very useful document from 1954 listing the ploidy (gene count) of many of the roses up to that time. Many of the varieties listed are OGR's. Bear in mind that I have not completed this document, so there will be additions made to it as time allows.
One of the many excellent articles on rose breeding by Ralph Moore: Striping in roses.
In his essay entitled "Out Of China", Ralph Moore discusses the influence the small China roses have had in his breeding work of the past 60 years.
Ralph Moore wrote this 1974 article in the ARS magazine about breeding new miniatures.
An article by Edward B. Le Grice on the Inheritance of color in Roses.
A document by George Schoener, and others, on Breeding With Rosa gigantea.
A useful article by Dr. Malcolm Manners on the sucessful germination of rose seed.
An article listing the ploidy (gene count) of most of the species roses used in breeding.
On Karl King's website, whcih is a rich collection of plant breeding information, you can read another important article by Ralph Moore on the Breeding of Miniature Moss Roses.
Edward B. Le Grice wrote this article on the Inheritance Of Unusual Colors in Roses.
Roy Shephard wrote a very good article on the ABC's of rose breeding for the ARS Annual. This is a very good beginners article.
Dr. Eileen W. Erlanson Macfarlane wrote an excellent article on the use of American rose species in a breeding program.