Christensen T, Riis AH, Hatch EE, Wise LA, Nielsen MG, Rothman KJ, Toft Sorensen H, Mikkelsen EM. Costs and efficiency of online and offline recruitment methods: a web-based cohort study. J Med Internet Res. 2017 Mar 1;19(3):e58. doi: 10.2196/jmir.6716
Gray-Little B, Williams VSL, Hancock TD. An item response theory analysis of the Rosenberg self-esteem scale. Pers Soc Psychol Bull. 1997;23(5):443-51. doi: 10.1177/0146167297235001
Webster AJ, Saville C, Church BM, Gnanasakthy A, Moss R. Some effects of different rearing systems on health, cleanliness and injury in calves. Vet J. 1985 Sep;141(5):472-83.
Webster AJ, Saville C, Church BM, Gnanasakthy A, Moss R. The effect of different rearing systems on the development of calf behaviour. Vet J. 1985 May;141(3):249-64.