[Opening ‘cow sheep cat dog’]
https://aplwiki.com/wiki/Simple_examples
[Conor Hoekstra ‘Algorithms as a Tool of Thought’] https://dyalog.tv/APLSeeds21/?v=GZuZgCDql6g
[Alan Perlis ‘In Praise of APL’]
https://apl.wiki/Alan_Perlis
[Key]
https://help.dyalog.com/latest/#Language/Primitive%20Operators/Key.htm
[Under]
https://code.jsoftware.com/wiki/Vocabulary/ampdot
[Nuvoc - J Vocabulary]
https://code.jsoftware.com/wiki/NuVoc
[J]
https://www.jsoftware.com
https://code.jsoftware.com/wiki/Guides/Getting_Started
[APL]
https://apl.wiki
https://tryapl.org
[Stephen Taylor ‘Discovering APL’]
https://aplwiki.com/wiki/Discovering_APL
[k]
http://shakti.com
https://estradajke.github.io/k9-simples/
[q]
https://code.kx.com/q/
https://code.kx.com/q/learn/