1. Doctoral Program, Faculty of Medicine, Universitas Airlangga, Surabaya Indonesia.
2. Department of Otorhinolaryngology Head and Neck Surgery, Faculty of Medicine, Universitas Airlangga/Dr Soetomo General Hospital, Surabaya Indonesia.
3. Department of Otorhinolaryngology Head and Neck Surgery, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia.
4. Department of Clinical Microbiology, Faculty of Medicine, Universitas Airlangga, Dr Soetomo General Hospital, Surabaya, Indonesia.