Determining the geographical area in which a formulary was first compiled presents problems similar to those involved in determining its date. Internal evidence is sometimes more promising: in some cases, formulae, while removing most specific details, did preserve the name of the place where the documents they were based on had been drawn up. When the name of a single city or monastery occurs often within the same collection, it seems logical to conclude that this would also have been where the whole formulary was originally compiled. This is the case for the collections associated with Angers, Clermont, Tours, Bourges, Laon, Murbach, Salzburg, St Gall, Saint-Denis, and collection C of the Reichenau formulary. Since this information often constitutes the only specific point of anchorage for these texts, the place of origin of these collections has been seen as key: Zeumer thus put together the Bourges collection out of several fragments precisely because they mentioned a common place of origin. Where the name of the location is not preserved, on the other hand, it is virtually impossible to recover the geographical context of a collection: many attempts have been made, for instance, to identify the area of activity of Marculf, who was infuriatingly thorough in removing specific details from his original documents, but none of these has been altogether successful.