Rick Wilson's Historical Flutes Page. Excellent, detailed information on the history of the flute. http://www.oldflutes.com
Terry McGee, Flute Maker. Flutes for Irish, Classical and Early Music. Especially the part 'Historical Flute Studies' is interesting. http://www.mcgee-flutes.com
David and Nina Shorey, Antique Flutes. David Shorey, who died in 2015, was probably one of the best authorities of the early French (Lot, Bonneville, Godfroy) and American (Haynes, Powell) Boehm system flutes. He documented his sales objects in detail. His wife Nina maintains the extensive website. http://www.antiqueflutes.com
Anne Pustlauk (Bruxelles) presents under 'Database' a wealth of original texts, fingerings and repertoire music for the Simple System Flute between 1790 and 1850 http://www.anne-pustlauk.de
Robert Bigio, London presents (among other interesting things) Christopher Steward's 'Early Flute Recordings' with numerous recordings of flutists mostly long passed away. The development and individuality of vibrato is fascinating. http://www.robertbigio.com
Nancy Hadden, From Swiss Flutes to Consorts: History, Music and Playing Techniques of the Transverse Flute in Switzerland, Germany and France ca. 1470-1640. PhD Thesis. Universitiy of Leeds, School of Music, 2010 http://etheses.whiterose.ac.uk/id/eprint/2581
MIMO - Musical Instrument Museum online. Database with actually more than 56,000 musical instruments - including 1,424 flutes - from museums and collections all over the world. Various search options. http://www.mimo-international.com
Michael Lynn, Oberlin/Ohio presents his collection of historical flutes, partly supplemented with sound samples. http://www.originalflutes.com
Museum für Musik, Basel. Largest collection of musical instruments in Switzerland; flutes are well represented. http://www.hmb.ch/museum-musik.html
Klingende Sammlung, Bern. The 'Playing Collection of Historic Musical Instruments' in Bern presents the collection of the instrument maker Karl Burri (1921 - 2003) with about 1,000 objects. Some of the instruments are playable. Some interesting flutes. http://www.klingende-sammlung.ch
Gesellschaft der Freunde alter Musikinstrumente (GEFAM). The 'Society of Friends of Ancient Music Instruments (GEFAM)' has been founded in Zurich in 1951. International organization, mainly active in the German-speaking world. Own publication GLAREANA. http://www.gefam.ch
Association des Collectionneurs d'Instruments à Vent (ACIMV). Founded 1987 in Paris. Own publication LARIGOT. http://www.acimv.fr
Società Italiana del Flauto Traverso Storico (S.I.F.T.S). Founded 1996 in Bologna. Own publication Bolletino della S.I.F.T.S. http://www.cidim.it
Galpin Society, UK. Founded 1946. Own publication Galpin Society Journal (1x/a) and Newsletter (3x/a).http://www.galpinsociety.org
American Musical Instrument Society (AMIS). Founded 1971. Own publication Journal of the American Musical Instrument Society (1x/a) and Newsletter (2x/a). http://www.amis.org
And also…
…some links which have nothing to do with the history of the flute, but with my own ‘history’: see 'Biography'