young man: https://pxhere.com/en/photo/1046502 No attribution required
teenagers:https://commons.wikimedia.org/wiki/File:Teenagers_in_Moscow.jpg By Alagich Katya [CC BY 2.0 (https://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons
middle aged: https://pixabay.com/en/bald-middle-aged-goatee-man-beard-583776/ No attribution required
old man: https://www.flickr.com/photos/thomasleuthard/5198470559 by https://www.flickr.com/photos/thomasleuthard/ https://creativecommons.org/licenses/by/2.0/
laural hardy: https://commons.wikimedia.org/wiki/File:Laurel_and_Hardy.png By Hal Roach Studios (Self-scanned) [Public domain], via Wikimedia Commons
medium build: https://www.flickr.com/photos/chrishunkeler/8049103309 By https://www.flickr.com/photos/chrishunkeler/ https://creativecommons.org/licenses/by-sa/2.0/
strong https://commons.wikimedia.org/wiki/File:Sebastian_Kowalczyk.JPG By Artur Andrzej [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0) or GFDL (http://www.gnu.org/copyleft/fdl.html)], from Wikimedia Commons
tall short: https://commons.wikimedia.org/wiki/File:Tall_woman_and_short_man.png by https://commons.wikimedia.org/wiki/User:Azerfghj https://creativecommons.org/licenses/by-sa/4.0/deed.en
long hair: https://www.flickr.com/photos/25697729@N08/22573033059 By https://www.flickr.com/photos/25697729@N08/ https://creativecommons.org/licenses/by/2.0/
short hair: https://commons.wikimedia.org/wiki/File:%C5%A0tenclov%C3%A1-Ivana-2012.jpg By NoJin [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)], from Wikimedia Commons
curly hair: https://www.flickr.com/photos/hourig94/6855257661 By https://www.flickr.com/photos/hourig94/ https://creativecommons.org/licenses/by/2.0/
wavy hair: https://www.maxpixel.net/Long-Blonde-Wavy-Hair-Hairstyle-Curls-Woman-490403 https://creativecommons.org/publicdomain/zero/1.0/deed.en
straight hair: https://www.pexels.com/photo/adult-back-beautiful-people-beauty-413751/ No attribution required
baldy: https://www.flickr.com/photos/vancouverfilmschool/4689257378 By https://www.flickr.com/photos/vancouverfilmschool/ https://creativecommons.org/licenses/by-sa/2.0/
beard: https://commons.wikimedia.org/wiki/File:M%C3%A5rten_Eskil_Winge_-_Portrait_of_a_Bearded_Man_-_A_I_749_-_Finnish_National_Gallery.jpg [Public domain or CC0], via Wikimedia Commons
moustache: https://commons.wikimedia.org/wiki/File:The_Handlebar_(Moustache)_Club_-_LONDON_-_07-03-2013_cropped.jpg By Eduardo Gaviña from Bilbao, PAIS VASCO [CC BY-SA 2.0 (https://creativecommons.org/licenses/by-sa/2.0)], via Wikimedia Commons
blonde https://pixabay.com/en/blonde-portrait-selfie-smile-model-1180343/ No attribution required
brunnete https://pxhere.com/en/photo/943372 No attribution required
black: https://www.maxpixel.net/Portrait-Blue-Eyes-Black-Hair-Girl-1271232 https://creativecommons.org/publicdomain/zero/1.0/deed.en
grey: https://www.pexels.com/photo/woman-carrying-flowers-closeup-photo-1035688/ No attribution required
young woman: https://www.maxpixel.net/Smiling-Girl-Smile-Woman-Beautiful-Young-Female-1687993 https://creativecommons.org/publicdomain/zero/1.0/deed.en
middle aged man: https://pixabay.com/en/right-view-man-middle-age-por-eyes-210380/ No attribution required
skin complextion: https://www.flickr.com/photos/saffy_suppi/5435872761 By https://www.flickr.com/photos/saffy_suppi/ https://creativecommons.org/licenses/by/2.0/