Wilson, P., O'Donnell, M., & Voelkel, B. (1957). A vocabulary preprimer workbook for Skip along, Under the sky, Open the door, and High on a hill. Row, Peterson and Company.

Wilson, Phyllis, Mabel O'Donnell, and Betty Voelkel. A Vocabulary Preprimer Workbook for Skip Along, Under the Sky, Open the Door, and High on a Hill. Evanston, Illinois ; White Plains, New York: Row, Peterson and Company, 1957.

Wilson, Phyllis, et al. A Vocabulary Preprimer Workbook for Skip Along, Under the Sky, Open the Door, and High on a Hill. Row, Peterson and Company, 1957.