References/Notes/Attributions:
Source
J.C. Gower and D.J. Hand (1996) Biplots Chapman & Hall Table 9.1. Quoted as from:
R.W. Summers, L.G. Underhill, D.J. Pearson and D.A. Scott (1987) Wader migration systems in south and eastern Africa and western Asia. Wader Study Group Bulletin 49 Supplement, 15–34.