APA (7th ed.) Citation
(1989). XXVI Colloguium Spectroscopicum Internationale. Volume VI.
Chicago Style (17th ed.) Citation
XXVI Colloguium Spectroscopicum Internationale. Volume VI. Sofia, 1989.
MLA (9th ed.) Citation
XXVI Colloguium Spectroscopicum Internationale. Volume VI. 1989.
Warning: These citations may not always be 100% accurate.