Footnote ai

^aiSee Voss et al. 2004; Wallace et al. 2004.

Voss, M., P. Croot, K. Lochte, M. Mills, and I. Peeken. 2004. Patterns of nitrogen fixation along 10°N in the tropical Atlantic. Geophys. Res. Lett. 31(23), L23S09, doi:10.1029/2004GL020127.

Wallace, D. W. R., and H.W. Bange. 2004. Introduction to special section: Results of the Meteor 55: Tropical SOLAS Expedition. Geophys. Res. Lett. 31, L23S01, doi:10.1029/2004GL021014.