APA (7th ed.) Citation

Gas Natural SDG. (1992). Informe Anual. Gas Natural.

Chicago Style (17th ed.) Citation

Gas Natural SDG. Informe Anual. Barcelona [etc.]: Gas Natural, 1992.

MLA (9th ed.) Citation

Gas Natural SDG. Informe Anual. Gas Natural, 1992.

Warning: These citations may not always be 100% accurate.