1. A review of methods for the demetallization of residual fuel oils;Ali;Fuel Process Technol,2006
2. Almarza R. Oilfields of Venezuela. In: PDVSA-Intevep. Geological Code of Venezuela; 1997. .
3. ASTM D287-92. Standard test method for API gravity of crude petroleum and petroleum products (Hydrometer Method). In: Petroleum Products and Lubricants (III), Vol. 05.03, West Conshohocken: ASTM International; 2006. p. 8.
4. ASTM D5708-05. Standard test methods for determination of nickel, vanadium, and iron in crude oils and residual fuels by inductively coupled plasma (ICP) atomic emisión spectrometry. In: Petroleum Products and Lubricants (III), vol. 05.03, West Conshohocken: ASTM International; 2006. p. 8.
5. Azuaje V. Geochemical characterization of crude oils from Marcelina reservoir in Alturitas Field using biomarkers. Maracaibo: MSc Thesis, University of Zulia; 2006.