Treasure books, out of New York, published around 1954-1957. Several volumes are excisting, allthough I am not sure how many exactly. Most of the time they are more recognizeable on the publishing year. Book one is numbered 874 in de childbook series. Valuable books.

1:In the days of King Arhur part 1.
2:In the days of King Arhur part 2.

The 1954 issue. USD 45

The 1957 issue USD 45