Distribution map of Alnus incana subsp. incana (gray alder).
     Native continuous range
✖ Native isolated population
▲ Introduced and naturalized (synanthropic)
Caudullo, G., Welk, E., San-Miguel-Ayanz, J., 2017. Chorological maps for the main European woody species. Data in Brief 12, 662-666. DOI: 10.1016/j.dib.2017.05.007
Data: https://doi.org/10.6084/m9.figshare.5100727
References:

Botanical Society of Britain &amp; Ireland. BSBI big database. Accessed in September 2016.
Grossgeim, A. A., 1945. Flora of Caucasus Vol 3. Academy of Sciences of the USSR, Azerbaijan branch. Baku (In Russian)
GBIF.org, 2016. Artdata. DOI: 10.15468/dl.vhlsf9
GBIF.org, 2016. Botanical Society of the British Isles - Vascular Plants Database additions since 2000. DOI: 10.15468/dl.wzy04e
GBIF.org, 2016. Botanical Society of the British Isles - Vascular Plants Database. DOI: 10.15468/dl.c7xheb
GBIF.org, 2016. Dutch Vegetation Database (LVD). DOI: 10.15468/dl.km20zh
GBIF.org, 2016. Fieldjournal.org observation database. DOI: 10.15468/dl.qfbdxi
GBIF.org, 2016. FloVegSI - Floristical and fitocenological database of ZRC SAZU. DOI: 10.15468/dl.emozjq
GBIF.org, 2016. Flora von Deutschland (Phanerogamen). DOI: 10.15468/dl.jhwqco
GBIF.org, 2016. Florabank1 - A grid-based database on vascular plant distribution in the northern part of Belgium (Flanders and the Brussels Capital region). DOI: 10.15468/dl.t9ewq8
GBIF.org, 2016. Floristic Databases of Mecklenburg-Pomerania - Higher Plants. DOI: 10.15468/dl.ttbnoc
GBIF.org, 2016. Herbarium of Jyväskylä University Museum. DOI: 10.15468/dl.qlmmfd
GBIF.org, 2016. INPN - Données flore des CBN agrégées par la FCBN. DOI: 10.15468/dl.gkp7wm
GBIF.org, 2016. Institute of Dendrology PAS, Flora of Sudety Mountains. DOI: .15468/dl.kybkpr
GBIF.org, 2016. Karl Franzens University of Graz, Insitute for Botany - Herbarium GZU. DOI: 10.15468/dl.4ok78i
GBIF.org, 2016. National System of Protected Areas in Poland - Plants. DOI: 10.15468/dl.ym4vmn
GBIF.org, 2016. Norwegian Species Observation Service. DOI: 10.15468/dl.6domy8
GBIF.org, 2016. Occurrence Data of Vascular Plants collected or compiled for the Flora of Bavaria. DOI: 10.15468/dl.olxxvo
GBIF.org, 2016. Sistema de Información de la vegetación Ibérica y Macaronésica. DOI: 10.15468/dl.m8zdd8
GBIF.org, 2016. University of Vienna, Institute for Botany - Herbarium WU. DOI: 0.15468/dl.x5raqx
GBIF.org, 2016. Vascular plants in Denmark recorded under the The Nationwide Monitoring and Assessment Programme for the Aquatic and Terrestrial Environments (NOVANA). DOI: 10.15468/dl.hnqokh
Hultén, E., 1971. Atlas över växternas utbredning i Norden, 2nd edition. Generalstabens litografiska anstalts förlag, Stockholm.
Hultén, E., Fries, M., 1986. Atlas of North European vascular plants (North of the Tropic of Cancer), Vols. I-III. Koeltz scientific books. ISBN 3874292630
Jalas, J., Suominen, J.(Eds.), 1976. Atlas Florae Europaeae: distribution of vascular plants in Europe Vol. 3 Salicaceae to Balanophoraceae. Committee for Mapping the Flora of Europe and Societas Biologica Fennica Vanario, Helsinki.
Meusel, H., Jäger, E. J., Weinert, E. (Eds.), 1965. Vergleichende Chorologie der Zentraleuropäischen Flora, Band I. Gustav Fischer Verlag, Jena.
NetPhyD: Deutschlandflora WebGIS. Floristische Verbreitungskarten in Deutschland. Accessed in September 2016.
Nikolić, T. (Ed.), 2015. Flora Croatica Database. Faculty of Science, University of Zagreb. Accessed in September 2016.
Sokolov  S. I., Svjaseva  O. A., Kubli  V. A., 1980. Areas of distribution of trees and shrubs in the USSR, vol 1. Nauka, Leningrad. (In Russian)
Tela Botanica. eFlore. Accessed in September 2016.
Giovanni Caudullo