L.M. Kriegsman, D.G.A.M. Aerden, R.J. Bakker, S.W.J. den Brok and P.M.T.M. Schutjens 1989. Variscan tectonometamorphic evolution of the eastern Lys-Caillaouas massif, Central Pyrenees - evidence for late orogenic extension prior to peak metamorphism. Netherlands Journal of Geosciences. (Jan. 1989), 323-333.