Where was Electronic Labyrinth: THX 1138 4EB filmed?

1967 film by George Lucas

Electronic Labyrinth: THX 1138 4EB (1967) was filmed in Los Angeles, University of California, Los Angeles, Los Angeles International Airport, University of Southern California and Van Nuys Airport, 5 places named in its Wikipedia article, in the United States. Wikidata records no filming location for it at all, so the article is the only recorded source. Each place says where its claim comes from.

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