Não informado. (2018). Ophthalmic Optician. British Optical Association.
Lua i Stíl Chicago (17ú heag.)Não informado. Ophthalmic Optician. London: British Optical Association, 2018.
Lua MLA (8ú heag.)Não informado. Ophthalmic Optician. British Optical Association, 2018.
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