Last month there was a post asking why some "constant" varieties did not appear on all panes of a particular stamp.
There was a feature in the March-April 2014 edition of the Elizabethan Study Group's newsletter
Corgi Times that explains why, via an excellent illustration.
The stamp in question is the 1972 Krieghoff issue, well known for it's constant varieties. The illustration shows how the stamps were printed in sheets of 200, which were later cut into 4 panes of 50, the format they were sold at post offices.
Enlargements of some (not all) varieties are shown, along with where they appear on the sheet.
Here is a link to the PDF, permission granted by the editor of Corgi Times.
http://www.adminware.ca/esg/corgiti...rieghoff.pdfThe Elizabethan Study Group is an excellent source of information for those who collect modern Canadian stamps and varieties.
Information on membership is here:
http://www.adminware.ca/esg