(1981). [Clock face, for teaching children to tell time]. [publisher not identified].
Chicago Style (17th ed.) Citation[Clock Face, for Teaching Children to Tell Time]. [Place of publication not identified]: [publisher not identified], 1981.
MLA (9th ed.) Citation[Clock Face, for Teaching Children to Tell Time]. [publisher not identified], 1981.
Warning: These citations may not always be 100% accurate.