Muhammad Khan; Syed Shahzad Ali; Rabail Rani Soomro. ORIGINAL ARTICLE: Efficacy of C1-C2 Sustained Natural Apophyseal Glide (SNAG) Versus Posterior Anterior Vertebral Mobilization (PAVMs) in the Management of Cervicogenic Headache. J. Basic Appl. Sci. 2014, 10, 226-230.