Galeopsis (Ladanum), Reichenb.

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1972, Flora Europaea. Volume 3. Diapensiacea to Myoporaceae, Cambridge: Cambridge University Press : 146

Subgen. Ladanum Reichenb. Vegetative parts, bracteoles and calyx with soft, crispate or patent hairs, and frequently also with glandular hairs, but without rigid yellowish hairs; stem 4-angled or terete, not swollen at the nodes.