Não informado. (1959). British journal of non-destructive testing. Non-Destructive Testing Society of Great Britain.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. British Journal of Non-destructive Testing. Leigh-on-Sea, Inglaterra: Non-Destructive Testing Society of Great Britain, 1959.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. British Journal of Non-destructive Testing. Non-Destructive Testing Society of Great Britain, 1959.
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