1930s. This is the actual example shown in the Hake's Pop Culture Guide. Set of six, each 10" long by 2.5" wide printed on front. Three promote Corn Flakes, two promote Rice Krispies, one promotes Pep Bran Flakes. Each has text with matching graphics. Includes Old King Cole, Little Boy Blue, Mary Had a Little Lamb, Humpty Dumpty, Old Mother Hubbard, Tom the Piper's Son. Each has lt. vertical center fold but all are still Exc. Rarely found as a set. Guide price is $100 each in NM.