Poulos C, Riewpaiboon A, Stewart JF, Clemens J, Guh S, Agtini M, Anh DD, Baiqing D, Bhutta Z, Sur D, Whittington D. Cost of illness due to typhoid fever in five Asian countries. Trop Med Int Health. 2011 Mar 1;16(3):314-23.
McKenna SP, Doward LC. How should we measure quality of life in ankylosing spondylitis? Rheumatol Pract. 2008;6(2):12-4.
Phanikumar CV, Maitra B. Modeling willingness-to-pay values for rural bus attributes under different trip purposes. JTRF. 2006;45(2):31-44. doi: 10.22004/ag.econ.206787