Mai, A. C. G., and I. M. de L. Rosa. “Ecological Aspects of the Seahorse Hippocampus Reidi in the Camurupim/Cardoso Estuary, Piauí State, Brazil, As Subsidies for the Implementation of an Environmental Protection Area”. Biota Neotropica, vol. 9, no. 3, Sept. 2009, //www.biotaneotropica.org.br/BN/article/view/526.