I have bought things other than language books. There are a number of interesting books that end up at the library book sale. One of them was this copy of the 13th book from the Nancy Drew series, The Mystery of the Ivory Charm by Carolyn Keene, first published in 1936.
I bought it for...a dollar? I think? The librarian I paid down at the circulation desk was always really weird toward me, acting like I was suspicious whenever I bought something and I remember she actually went and checked with another librarian to make sure that really was the price. There are the shelves where you pay by type of book and then another section where the books have price stickers because they are more valuable. I think she thought I'd taken the sticker off to get it at the normal hardback fiction price. I am so glad she no longer works there. I don't know what I did to make her think I was some sort of cheat.
Anyway. The initials of whoever owned it were S.A.
Well, not actually by Carolyn Keene. These adolescent book series were ghostwritten by a number of different people, apparently, and this one was penned by Mildred Wirt Benson. It's 216 pages and 19cm x 13cm. There's a picture endpaper and one picture at the start of the book.
The illustrations were done by Russell H. Tandy and the original edition had more and in color from what I've found. This particular copy must have been printed in about 1954 or so because there is a list of other books in the series and one for the Dana Girls Mystery Stories and both of the last books listed were published in 1953. The dust jacket did not come with the book.
It was sold at The Book Shop in Fitchburg, MA.
It appears to have been at 536 Main St. and opened in 1952 by a man named Alexander Krysil and run until his death in 2014. Here's a link to a picture of their window display in the 1958 Billboard.
I have never read a Nancy Drew book in my life.