Chilson, P. B., Frick, W. F., Stepanian, P. M., Shipley, J. R., Kunz, T. H., & Kelly, J. F. (2012). Estimating animal densities in the aerosphere using weather radar: To Z or not to Z? Ecosphere, 3(8), 1-19. doi:10.1890/es12-00027.1.