T. G. Tutin, N. A. Burges, A. O. Chater, J. R. Edmondson, V. H. Heywood, D. M. Moore, D. H. Valentine, S. M. Walters & D. A. Webb, Flora Europaea 1, ed. 2. 1993
but modified and names used differing
1Ochreae and petioles densely hairy
1'Ochreae and petioles glabrous or sparsely hairy
2Spikes lax and slender, with each flower distinctly visible; ochreae strongly ciliate
2'Spikes dense and stout, with the flowers crowded and overlapping; ochreae entire or shortly ciliate
3Peduncles with numerous subsessile yellow glands; surface of ochrea glabrous
3'Peduncles without glands; surface of ochrea with scattered hairs