SpringerLink (Online service), Jekeli, C., Bastos, L., & Fernandes, J. (2005). Gravity, Geoid and Space Missions: GGSM 2004 IAG International Symposium Porto, Portugal August 30 – September 3, 2004. Springer Berlin Heidelberg.
Παραπομπή σε μορφή Chicago (17η εκδ.)SpringerLink (Online service), Christopher Jekeli, Luisa Bastos, και Joana Fernandes. Gravity, Geoid and Space Missions: GGSM 2004 IAG International Symposium Porto, Portugal August 30 – September 3, 2004. Berlin, Heidelberg: Springer Berlin Heidelberg, 2005.
Παραπομπή σε μορφή MLA (8th εκδ.)SpringerLink (Online service), et al. Gravity, Geoid and Space Missions: GGSM 2004 IAG International Symposium Porto, Portugal August 30 – September 3, 2004. Springer Berlin Heidelberg, 2005.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.