BibTex format
@article{Koo:2004:10.1103/PhysRevA.69.043402,
author = {Koo, K and Sudbery, J and Segal, DM and Thompson, RC},
doi = {10.1103/PhysRevA.69.043402},
journal = {PHYSICAL REVIEW A},
title = {Doppler cooling of Ca<SUP>+</SUP> ions in a Penning trap -: art. no. 043402},
url = {http://dx.doi.org/10.1103/PhysRevA.69.043402},
volume = {69},
year = {2004}
}