Photogrammetry of blue whales with an unmanned hexacopter. Issue 4 (6th May 2016) - Durban, John W.; Moore, Michael J.; Chiang, Gustavo; Hickmott, Leigh S.; Bocconcelli, Alessandro; Howes, Gloria; Bahamonde, Paulina A.; Perryman, Wayne L.; LeRoi, Donald J.