Posted By:
Scot Reader
An advanced collector who I respect very much has noted that he has searched in vain for decades for some of the front/back combinations listed in the checklist at the end of the manuscript. This does not surprise me and I expect that more than a few of the listed combinations will never be found. The checklist resulted from findings in a survey that I conducted. Due to a limited survey sample, formulating the checklist required drawing inferences from patterns witnessed in the survey. By drawing such inferences, I was able to categorically rule-out groups of front/back combinations that were included in earlier checklists; however, I was not able to rule-out any individual front/back combinations that do not exist for anomalous reasons. The checklist in the manuscript is therefore likely somewhat overinclusive; however, it should be considerably less overinclusive than prior checklists.