Columbia subject headings:
Blatz, William E., 1895-1964.
Child development--Canada--History.
Child psychology--History.
Psychologists--Canada--Biography.
Harvard subject headings:
Blatz William E., 1895-1964.
Child development--Canada--History.
Child psychologists--Canada--Biography.
Child psychology--Canada--History.
Princeton subject headings:
Blatz, William E., 1895-1964.
Child development--Canada--History.
Child psychologists--Canada--Biography.
Child psychology--History.