HARDANI, R. N.; ROCMAH, L. I. Increasing The Ability To Recognize Number Symbols Through The Activities Of Playing Snakes And Stairs For Children Of Group A In Tk Aisyiyah Busthanul Athfal 6 Candi. Academia Open, v. 5, p. 10.21070/acopen.5.2021.2221, 23 Aug. 2021.