Age of the magnetically active WW Psa and TX Psa members of the β Pictoris associationS. Messina, R. Santallo, T. G. Tan, P. Elliott, G. A. Feiden, A. Buccino, P. Mauas, R. Petrucci and E. JofréA&A, 601 (2017) A54DOI: https://doi.org/10.1051/0004-6361/201628514