Jacquemin B, Schikowski T, Carsin AE, Hansell A, Kramer U, Sunyer J, Probst-Hensch N, Kauffmann F, Kunzli N. The role of air pollution in adult-onset asthma: a review of the current evidence. Semin Resp Crit Care. 2012 Dec;33(6):606-19. doi: 10.1055/s-0032-1325191
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