Sinaga, Sarma Eko Natalia. “The Effect of Health Promotion in Improving the Attitudes of Health Students in Carrying Out the Health Protocol to Prevent Covid-19”. Jurnal Ners Dan Kebidanan (Journal of Ners and Midwifery), vol. 8, no. 2, Aug. 2021, pp. 178-83, doi:10.26699/jnk.v8i2.ART.p178-183.