If one is looking for a facility which has a book for which one is seeking, try www.worldcat.org.  Although nothing showed for the title "The Marvel Family: The Path to Delaware",  a search for Marvel found "The Hargadines and other Delaware and Maryland families : (includes data on Aron, Broadway, Lowber, Manlove, Marvel, Seward, Sipple)", also by Donald Virdin and a search under Virdin came up with "Some Pioneer Delaware Families". Worldcat is a useful tool as it searches for books (and other materials) nationwide and when one enters one's zipcode, it tells how many miles away each library on the list is from that zip.  If one already has the page number of the book citation, even if the closest library were still too far to visit, one could order the page(s). Of course, worldcat's usefulness depends upon the library entering the data and at least one local facility is lax on entering its holdings, which is a shame.   Becky M