It is as yet
impossible to give precise information about the distribution of
this species in the Region as it has long been confused
with E. helleborine. Flowers in June from 500 to
-CRESCENTINI, R. & J.M.I.
KLAVER, Orchidee Spontanee della Provincia Pesaro e Urbino, con
osservazioni sulle specie delle Marche, Pesaro, 1997 (p.88).
-KLAVER, J.M.I., "Distribution
of the Orchidaceae of the Province Pesaro-Urbino (Central-East Italy)",
AHO Baden-Württemberg 23 (4), 1991, pp.557-747 (p.597).