COKER, DAWNE. "T4T Perceptual Subitizing Cards". OER Commons. Institute for the Study of Knowledge Management in Education, 05 Jul. 2019. Web. 26 Dec. 2024. <https://goopennc.oercommons.org/authoring/594-t4t-perceptual-subitizing-cards>.
COKER, D. (2019, July 05). T4T Perceptual Subitizing Cards. OER Commons. Retrieved December 26, 2024, from https://goopennc.oercommons.org/authoring/594-t4t-perceptual-subitizing-cards.