Authors: van den Boom, PPG Coppins, BJ

Citation: Ppg. Van Den Boom et Bj. Coppins, Micarea viridileprosa sp nov., an overlooked lichen species from Western Europe, LICHENOLOGI, 33, 2001, pp. 87-91

Authors: Giralt, M Mayrhofer, H van den Boom, PPG Elix, JA

Citation: M. Giralt et al., Rinodina turfaceoides, a new corticolous, blastidiate species from the Iberian Peninsula, LICHENOLOGI, 33, 2001, pp. 97-102

Authors: van den Boom, PPG Etayo, J

Citation: Ppg. Van Den Boom et J. Etayo, Two new sorediate species of lichens in the Catillariaceae from the Iberian Peninsula, LICHENOLOGI, 33, 2001, pp. 103-110

Authors: van den Boom, PPG Giralt, M

Citation: Ppg. Van Den Boom et M. Giralt, Contribution to the flora of Portugal, lichens and lichenicolous fungi II, NOVA HEDWIG, 68(1-2), 1999, pp. 183-196