BPI WORLDWIDE. QUESTIONS & ANSWERS INVENTIONS AND DISCOVERIES. BPI WORLDWIDE.
Chicago Style aipamenaBPI WORLDWIDE. QUESTIONS & ANSWERS INVENTIONS AND DISCOVERIES. UNITED KINGDOM: BPI WORLDWIDE.
MLA aipamenaBPI WORLDWIDE. QUESTIONS & ANSWERS INVENTIONS AND DISCOVERIES. BPI WORLDWIDE.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.