L.M. Kriegsman; D.G.A.M. Aerden; R.J. Bakker; S.W.J. den Brok; P.M.T.M. Schutjens. Variscan Tectonometamorphic Evolution of the Eastern Lys-Caillaouas Massif, Central Pyrenees - Evidence for Late Orogenic Extension Prior to Peak Metamorphism. njg 1989, 323-333.