“Is Stress Levels And Coping Mechanism Becomes Factor That Affected Challanging of Mother That Have Children With Mental Retardation”. 2017. INTERNATIONAL JOURNAL OF NURSING AND MIDWIFERY SCIENCE (IJNMS) 1 (1): 39-45. https://doi.org/10.29082/IJNMS/2017/Vol1/Iss1/32.