The major US manufacturer of acoustic piano keyboards with narrower keys: www.steinbuhler.com.
The Steinbuhler company was converted into a non-profit Foundation in 2018, called the DS Standard Foundation Inc: http://www.dsstandardfoundation.org/. Facebook: https://www.facebook.com/dsstandardfoundation/
Pianists for Alternatively Sized Keyboards (PASK): http://www.paskpiano.org. On Facebook: Accessible to all: http://www.facebook.com/pask.piano/. Also a closed group: https://www.facebook.com/groups/PASK.Action/. See also: PASK
Other links to social media are included at the bottom of this page.
A website focusing on technological solutions and resources for technicians and potential customers called Technicians for Alternatively Sized Keyboards: www.taskpiano.org
Thwere are also TASK Facebook pages:
A community page accessible to all: https://www.facebook.com/TASKPiano/
A closed group restricted to piano professionals: www.facebook.com/groups/TASKPiano/
Dr Carol Leone from Dallas, Texas – Chair of Keyboard Studies at SMU Meadows School of the Arts in Dallas, internationally recognized performing artist, teacher, lecturer, and author, and one of the world’s leading researchers and proponents of ergonomic piano keyboards to promote a pianist’s wellness: www.carolleone.com
A group of academics in Germany and Switzerland is continuing with important research of the late Dr Christoph Wagner relating to the hands of pianists and violinists. Three websites describe this work: http://www.hand-und-instrument.de/E_index.html; http://www.hand-und-instrument.de/E_pragm-handeinschaetzung.html; http://www.christoph-wagner-musikphysiologie.de/Links.html. For further information, contact Professor Ulrike Wohlwender from the University of Music and the Performing Arts in Stuttgart: firstname.lastname@example.org. See Earlier hand span studies for some of Wagner’s summary statistics.
Pianist Eliana Yi, from Dallas Texas, has shared her insights about playing Steinbuhler keyboards while studying at SMU Meadows School of the Arts. http://www.elianayipiano.com/single-post/2016/1/31/Making-things-easier-for-the-first-time-in-forever
Pianist Tiffany Goff, from Cleveland Ohio, has a blog: www.skinnykeys.tumblr.com
This website (www.smallpianokeyboards.org) has been translated into Japanese here:
For an interesting perspective on the history of attempts to gain support for alternatively sized keyboards in Japan, see: http://littlehands782.blogspot.com.au/2014/01/the-history-and-attitudes-to-smaller.html
Pianist Renata Bittencourt, from Paris, has a website (in French): http://www.lespetitsclaviers.sitew.fr/#ACCUEIL.A
Pianist Grace Choi has written this personal story: Thoughts for Pianists with Small Hands: A Testimonial by Grace Choi. It is the second blog on this page: http://www.thehealthymusicianproject.com/blog
From Jess Johnson, Professor of Piano and Piano Pedagogy at the University of Madison-Wisconsin, where there is a DS5.5® keyboard installed. http://feelingthesound.org/2015/07/21/small-hands-big-heart/
Sydney teacher and Suzuki teacher trainer, Erica Booker, has pianos with alternatively sized keyboards in her studio. https://ericabookerpiano.com/