Indian Ektara:
https://www.uncoveringsound.com/ektara/
Ichigenkin: https://www.ichigenkin.com/
Tuntune instrument: https://indianculture.gov.in/musical-instruments/tat-vadya/tuntune
Khamak – Indian: https://chandrakantha.com/music-and-dance/instrumental-music/indian-instruments/khamak/
K’ni:
https://www.soundsofangkor.org/english/ethnic-music/mouth-resonator-fiddle/
Book “Africa and the Blues” at pages: 16 and 100
Berimbau:
https://centerforworldmusic.org/2015/06/world-music-instruments-the-berimbau/
Trong dat: https://youtu.be/RAqA0QHN2fI?t=265
The Origins of String Instruments (Musical Bow)
Traditional musical instruments in Namibia, Africa:
https://www.musicinafrica.net/fr/node/13711
[1]https://journals.lib.unb.ca/index.php/MC/article/view/30489/1882525830
[2]https://capoeirahistory.com/musical-bows/
http://mmaletsatsipro.co.za/blog/umakhweyana.html
https://www.vienamnhac.vn/vietnamese-music-space/museum/musical-instruments/tan-mang—chordophone
Book: The Vietnamese Đàn Bầu: A Cultural History of an Instrument in Diaspora
Physiology, Sleep Stages: National Library of Medicine
https://www.hfmt-hamburg.de/innovative-hochschule/spiic/