Asteroseismological constraints on the coolest GW Virginis variable star (PG 1159-type) PG 0122+200A. H. Córsico, M. M. Miller Bertolami, L. G. Althaus, G. Vauclair and K. WernerA&A, 475 2 (2007) 619-627DOI: https://doi.org/10.1051/0004-6361:20078145