Файл:Tratado de Optica.pdf

This image is in the public domain because it is a mere mechanical scan or photocopy of a public domain original, or – from the available evidence – is so similar to such a scan or photocopy that no copyright protection can be expected to arise. The original itself is in the public domain for the following reason:

Public domainPublic domainfalsefalse

	Това произведение е обществено достояние в държавите, в които срокът на авторското право е 100 години или по-малко след смъртта на автора. Това произведение е обществено достояние в Съединените американски щати, защото е било публикувано преди 1 януари 1924 година.
This file has been identified as being free of known restrictions under copyright law, including all related and neighboring rights.

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Note: This tag applies to scans and photocopies only. For photographs of public domain originals taken from afar, {{PD-Art}} may be applicable. See Commons:When to use the PD-Art tag.