Không rõ. (2000). Product Design and Development. NOTNXB.
Chicago Style aipamenaKhông rõ. Product Design and Development. NOTNXB, 2000.
MLA aipamenaKhông rõ. Product Design and Development. NOTNXB, 2000.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.