Geometric morphometrics and the anlysis of variations in facial form: robusticity of biological findings in relation to bilateral versus unilateral and missing landmarks.
Una Strand Vidarsdottir et Paul O'Higgins, Geometric morphometrics and the anlysis of variations in facial form: robusticity of biological findings in relation to bilateral versus unilateral and missing landmarks., Statistica, 61(2), 2001, pp. 315-333