The purple machine cancel handbook
By: by Robert M. Washburn and Carl R. Ditsch.
Contributors: Ditsch, Carl R.
Publisher: R.M. Washburn
Published: 1994
Place of publication: Skowhegan, Me. (P.O. Box 840 Skowhegan, Me. 04976)
Language: eng
Subjects: Cancellations (Philately) -- United States -- History.; Postmarks -- United States -- History.
Notes: Includes bibliographical references.