Maitra B, Dandapat S, Chintakayala P. Differences between the perceptions of captive and choice riders toward bus service attributes and the need for segmentation of bus services in urban India. J Urban Plan Dev. 2015 Jun;141(2).
Mangel AW, Wang J, Sherrill B, Gnanasakthy A, Ervin C, Fehnel SE. Urgency as an endpoint in irritable bowel syndrome. Gastroenterology Research. 2011 Feb 1;4(1):9-12.
Chintakayala PK, Maitra B. Modeling generalized cost of travel and its application for improvement of taxies in Kolkata. J Urban Plan Dev. 2010 Mar;136(1).