M., S., J., M., Sundaramurthi, I. and S., G. 2017. A study on prevalence and co-morbidity of bipolar and anxiety disorders in chronic headache patients. International Journal of Research in Medical Sciences. 5, 7 (Jun. 2017), 3038–3043. DOI:https://doi.org/10.18203/2320-6012.ijrms20172984.