"While the source-critical debate over Goodnight Moon never reached the heightened pitch of the argument over the Torah’s multiple authors ... the question of whether Goodnight Moon has one, three or more authors continues to keep scholars up past their bedtime. Can a work that clearly owes so much to the Ugaritic psalm, ‘I see the moon and the moon sees me,’ really have been written by a Manhattan socialite? Most scholars take Margaret Wise Brown” as stand-in for a postulated committee of at least three authors.
Clearly most of the book consists of a “doublet,” that is, two versions of the same tale repeated. For convenience, we designate the first section, which announced the existence of the objects in the room, as E; the second, in which the objects are greeted “Goodnight room....” is designated G. Yet the repeating motifs of the Cow Jumping over the Moon and the Three Little Bears speak to a separate awareness of European folktales....."
Excerpt from http://www.shmoozenet.com/yudel/mtarchives/pix/Sham05.pdf