| One hundred new species of lichenized fungi: a signature of undiscovered global diversity HT Lumbsch, T Ahti, S Altermann, GA De Paz, A Aptroot, U Arup, AB Peña, ... Phytotaxa 18, 1-127, 2011 | 269 | 2011 |
| The lichens of the Alps–an annotated checklist PL Nimis, J Hafellner, C Roux, P Clerc, H Mayrhofer, S Martellos, ... MycoKeys, 1, 2018 | 177 | 2018 |
| Lichen chimeras: DNA analysis suggests that one fungus forms two morphotypes D Armaleo, P Clerc Experimental mycology 15 (1), 1-10, 1991 | 158 | 1991 |
| Evolution of complex symbiotic relationships in a morphologically derived family of lichen‐forming fungi PK Divakar, A Crespo, M Wedin, SD Leavitt, DL Hawksworth, L Myllys, ... New Phytologist 208 (4), 1217-1226, 2015 | 144 | 2015 |
| Species concepts in the genus Usnea (lichenized Ascomycetes) P Clerc The Lichenologist 30 (4-5), 321-340, 1998 | 126 | 1998 |
| Synopsis of the genus Usnea (lichenized ascomycetes) in British Columbia, Canada P Halonen, P Clerc, T Goward, IM Brodo, K Wulff Bryologist, 36-60, 1998 | 117 | 1998 |
| Systematics of the Usnea fragilescens aggregate and its distribution in Scandinavia P Clerc Nordic Journal of Botany 7 (4), 479-495, 1987 | 114 | 1987 |
| Contribution à la révision de la systématique des usnées (Ascomycotina Usnea) d'Europe. I: Usnea florida (L.) Wiggl. emend. Clerc P Clerc Cryptogamie. Bryologie, lichénologie 5 (4), 333-360, 1984 | 104 | 1984 |
| Mycobiont-specific PCR primers for the amplification of nuclear ITS and LSU rDNA from lichenized ascomycetes H Döring, P Clerc, M Grube, M Wedin The Lichenologist 32 (2), 200-204, 2000 | 96 | 2000 |
| Les champignons lichénisés de Suisse: catalogue bibliographique complété par des données sur la distribution et l'écologie des espèces P Clerc Bryolich 19, 1-320, 2004 | 93 | 2004 |
| Saxicolous species of Usnea subgenus Usnea (lichenized ascomycetes) in North America P Clerc, MA Herrera-Campos Bryologist, 281-301, 1997 | 87 | 1997 |
| Usnea P Clerc Nordic lichen flora 4, 107-127, 2011 | 86 | 2011 |
| Rote Liste der gefährdeten Arten der Schweiz: baum-und erdbewohnende Flechten C Scheidegger, P Clerc BUWAL, 2002 | 80 | 2002 |
| Considerations and consequences of allowing DNA sequence data as types of fungal taxa JC Zamora, M Svensson, R Kirschner, I Olariaga, S Ryman, LA Parra, ... IMA fungus 9, 167-175, 2018 | 77 | 2018 |
| Pendulous species of Usnea from the temperate forests in Mexico MA Herrera-Campos, P Clerc, TH Nash III Bryologist, 303-329, 1998 | 74 | 1998 |
| A rapid and inexpensive method for the purification of DNA from lichens and their symbionts D Armaleo, P Clerc The Lichenologist 27 (3), 207-213, 1995 | 66 | 1995 |
| Notes on the genus Usnea Adanson. II P Clerc Bibliotheca Lichenologica 88, 79-90, 2004 | 65 | 2004 |
| The lichens of the Alps–an annotated checklist. MycoKeys 31: 1–634 PL Nimis, J Hafellner, C Roux, P Clerc, H Mayrhofer, S Martellos, ... | 56 | 2018 |
| Testing the use of ITS rDNA and protein-coding genes in the generic and species delimitation of the lichen genus Usnea (Parmeliaceae, Ascomycota) C Truong, PK Divakar, R Yahr, A Crespo, P Clerc Molecular Phylogenetics and Evolution 68 (2), 357-372, 2013 | 55 | 2013 |
| Pendulous Usnea species (Parmeliaceae, lichenized Ascomycota) in tropical south America and the Galapagos C Truong, JM Rodriguez, P Clerc The Lichenologist 45 (4), 505-543, 2013 | 53 | 2013 |
