Knowledge and Attitude towards Obstructive Sleep Apnea among Primary Care Physicians in Northern Regions of Saudi Arabia: A Multicenter Study oleh Abdullah N. Al-Rasheedi, Ashokkumar Thirunavukkarasu, Abdulhakeem Almutairi, Sultan Alruwaili, Hatem Alotaibi, Wasan Alzaid, Faisal Albalawi, Osama Alwadani, Ahmed Dilli