Παραπομπή σε μορφή APA (7η εκδ.)
International Conference on Ecological Protection of the Planet Earth (2nd : 2003 : Sofia, Bulgaria), Bulgaria. Technical University of Sofia. Environmental Technology and Management Laboratory, Greece. Bio-politics International Organization, Δημοκρίτειο Πανεπιστήμιο Θράκης, Ελλάδα. Διεθνές Κέντρο Ερευνών (ΔΙ.ΚΕ.Ε.), & Bulgaria. Ministry of Environment and Water. (2003). 2nd International Conference on ecological protection of the planet earth: Business forum - Investments in environment - the winning strategy. Bulgaria. Ministry of Environment and Water.
Παραπομπή σε μορφή Chicago (17η εκδ.)
International Conference on Ecological Protection of the Planet Earth (2nd : 2003 : Sofia, Bulgaria), Bulgaria. Technical University of Sofia. Environmental Technology and Management Laboratory, Greece. Bio-politics International Organization, Δημοκρίτειο Πανεπιστήμιο Θράκης, Ελλάδα. Διεθνές Κέντρο Ερευνών (ΔΙ.ΚΕ.Ε.), και Bulgaria. Ministry of Environment and Water. 2nd International Conference on Ecological Protection of the Planet Earth: Business Forum - Investments in Environment - the Winning Strategy. Bulgaria. Ministry of Environment and Water, 2003.
Παραπομπή σε μορφή MLA (9th εκδ.)
International Conference on Ecological Protection of the Planet Earth (2nd : 2003 : Sofia, Bulgaria), et al. 2nd International Conference on Ecological Protection of the Planet Earth: Business Forum - Investments in Environment - the Winning Strategy. Bulgaria. Ministry of Environment and Water, 2003.
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