Booklet issued by the North Yorkshire Moors Railway entitled 'An Illustrated History of the NYMR and its Railway Letter Service. Interleaved with NYMR Railway Letter Stamps', 1991. Issued on the 10th anniversary of the NYMR Railway Letter Service. Includes a history of the NYMR, a chronology of stamps issued by the NYMR letter service, and a short history of the railway letter service. With Certificate of Authenticity.