Edwards PET, Parsons GR, Myers KH. The economic value of viewing migratory shorebirds on the Delaware Bay: an application of the single-site travel cost model using on-site data. Hum Dimens Wildl. 2011;16(6):435-44. doi: 10.1080/10871209.2011.608180
Hooper SR, Roberts JE, Nelson LM, Zeisel S, Kasambira D. Preschool predictors of narrative writing skills in elementary school children. Sch Psychol Q. 2010 Mar;25(1):1-12.
Mirabelli MC, Zock JP, Bircher AJ, Jarvis D, Keidel D, Kromhout H, Norbäck D, Olivieri M, Plana E. Metalworking exposures and persistent skin symptoms in the ECRHS II and SAPALDIA 2 cohorts. Contact Dermatitis. 2009 May;60(5):256-63.
Vallano A, Mendoza G, Rodríguez A, Rebordosa C. Seguridad de los analgesicos y de los antiinflamatorios. Farm Hosp. 2004;157:23-31.