BibTex format
@article{Grop:2011:10.1109/TUFFC.2011.1998,
author = {Grop, S and Schaefer, W and Bourgeois, P-Y and Kersale, Y and Oxborrow, M and Rubiola, E and Giordano, V},
doi = {10.1109/TUFFC.2011.1998},
journal = {IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL},
pages = {1694--1697},
title = {Unprecedented Long-Term Frequency Stability With a Microwave Resonator Oscillator},
url = {http://dx.doi.org/10.1109/TUFFC.2011.1998},
volume = {58},
year = {2011}
}