Josep Balsach. mipaginapersonal
The Calc Machines (DIE RECHENMASCHINEN) E Martin
http://www.nzeldes.com/HOC/HOC_Core.htm
Arithmometre.com (Valéry Monnier)
mechanicalculator (Kees Nagtegaal)
digilander.libero.it/giuseppecaltagirone/index.
home.vicnet.net.au/~wolff/calculators/welcome.htm
ourworld.compuserve.com/homepages/Michel_Bardel
people.wiesbaden.netsurf.de/~ratz/default.htm
users.lewiston.com/ejorgens/office/index.htm
1.131.telia.com/~u13101111/collection.html#calc
geocities.com/SiliconValley/Horizon/1404/
geocities.com/SiliconValley/Park/7227/
museoscienza.org/ancora/Default.htm
officemuseum.com/calculating_machines_adders
or.uni-bonn.de/home/muuss/arithmeum/
ph-ludwigsburg.de/mathematik/mmm/
taswegian.com/MOSCOW/mechbystr.html
typewriter.net/museo/sala13.htm
uni-greifswald.de/~wwwmathe/RTS/node2
vintagecalculators.com/index.html
cruzio.com/~vagabond/ComptHome.html
cs.unc.edu/Outreach/vr/computer_museum/Gallery1page
Contributions to the History of Mechanical Calculation
Original Documents on the History of Calculators
Patent database (the great encyclopedia of mech calculating)
Mathematisches Maschinen-Museum
Ernie Jorgenson's Office Machine Americana
Recuerdos del Cálculo Mecánico
· Museu de la Tècnica de l'Empordà (Figueras, Spain)
· Deutsches Schreibmaschinen-Museum (Bayreuth, Germany)
· Schrijfm@chinemuseum (Belgium)
· Scryption (Holland)
· Stephan Beck (Switserland)
· Peter Mitterhoffer Schreibmaschinenmuseum(Italy)
· Deutsches Schreibmaschinen-Museum (Bayreuth, Germany)