Sarjeant and Stancliffe, 1996
From dinoflaj3
Sarjeant, W.A.S. and Stancliffe, R.P.W., 1996: The acritarch genus Polygonium, Vavrdová emend Sarjeant and Stancliffe 1994: a reassessment of its constituent species. Annales de la Société géologique de Belgique, v.117, no.2, p.355-369.