New improved narration, more details.
Dogger Bend Railway UP Big Boy
https://www.youtube.com/watch?v=4QIDehuFWq0&t=1s
gmpullman :D&H Alco PA
https://www.youtube.com/watch?v=G08t1O_jLwk&t=17s
baldwinloco12: Alco RS-1
https://www.youtube.com/watch?v=swGMrgj2Kfs&t=1558s
rollingswitch: Alco RS-3
https://www.youtube.com/watch?v=AJkGtczswTQ&t=2s
Alco 60 tonner William Hunter CC BY 2.0
https://en.wikipedia.org/wiki/List_of_ALCO_diesel_locomotive_classes#/media/File:1926_AlcoGEIngersoll-Rand_Boxcab_Locomotive_11.jpg
Alco DL 109
(DVD) New York, New Haven & Hartford Railroad Volume 1 - A & R Productions
Note: the original publishers website (www.classicrailroadvideos.com) seems to be defunct.
NW3
Wikicommons Akampfer CC BY-SA 3.0
https://commons.wikimedia.org/wiki/Category:EMD_NW3_locomotives_of_the_Great_Northern_Railway_(US)#/media/File:Great_Northern_Engine_In_Whitefish.jpeg
FM sub apposed piston engine 1 Atlant CC by 2.5
https://upload.wikimedia.org/wikipedia/commons/a/a4/Opposed_piston_engine_1.jpg
Trains sim classic (footage);
https://dovetailgames.com/
NPR 190
NOYB#1 CC BY 2.0
https://commons.wikimedia.org/wiki/Category:ALCO_PA_locomotives_of_the_Nickel_Plate_Road#/media/File:NKP-_190_(49348063763).jpg
Museum of the American Railroad D&H alco pa shell.
https://www.historictrains.org/projects/alco-pa-1-image-gallery
DL109 video
(DVD) New York, New Haven & Hratforad Railraod Voulume 1: A & R Producions
Website defunct, avalible from 3rd party retailers.
Alco PA's in mexico
(DVD) Those-Incredible-Alcos-Volume 1 (diesel dinosaur delights): Pentrex
https://pentrex.com/DVD-Those-Incredible-Alcos-Volume-1-DVD_ALCO1-DVD
Pacific Southwest Railway Museum: 244 prime mover
https://www.psrm.org/
The Museum of the American RailroadAlco PA under restoration pics https://www.historictrains.org/