https://repository.usu.ac.id/bitstream/handle/123456789/40791/RHINOSINUSITIS%20PADA%20ANAK2.pdf?sequence=1&isAllowed=y
https://simdos.unud.ac.id/uploads/file_penelitian_1_dir/cf64c36b65b16889be121b590e1a9ac3.pdf
http://eprints.undip.ac.id/56219/3/Surya_Dewi_Setyaningrum_22010113140153_Lap.KTI_Bab2.pdf
