Kustiawan, Winda, Arofah Sri Mulyani Mz Siregar, Khairunisa Harani Harahap, Muhammad Syahdan Khatib Pane, Putri Imelda, and Sarmila Haerani. 2023. “Breathing and Voice Exercise”. Jurnal Pendidikan Tambusai 7 (2):3673-81. https://doi.org/10.31004/jptam.v7i2.6710.