(1993). Distance Sampling. Chapman & Hall.
Dyfyniad Arddull ChicagoDistance Sampling. Chapman & Hall, 1993.
Dyfyniad MLADistance Sampling. Chapman & Hall, 1993.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.
(1993). Distance Sampling. Chapman & Hall.
Dyfyniad Arddull ChicagoDistance Sampling. Chapman & Hall, 1993.
Dyfyniad MLADistance Sampling. Chapman & Hall, 1993.