Brodtkorb T, Kogler GF, Arndt A. The influence of metatarsal support height and longitudinal axis position on plantar foot loading. Clin Biomech (Bristol, Avon). 2008;23(5):640-7.
Wilson MR, Van Houtven CH, Stearns S, Clipp EC. Depression and missed work among informal caregivers of older individuals with dementia. J Fam Econ Issues. 2007;28(4):684-98.
Parsley (Edwards) TL. Review of the phantom respondents: opinion surveys and political representation. J Off Stat. 1994;10(3):351-5.