Wichmann, G., J. Backer, T. Zuna-Kratky, K. Donnerbaum, and M. Rössler. “Age-Related Stopover Strategies in the Wood Sandpiper Tringa Glareola”. Ornis Fennica, vol. 81, no. 4, Dec. 2004, pp. 169–179, https://ornisfennica.journal.fi/article/view/133624.