G. E. Backus, Non-uniqueness of the external geomagnetic field determined by surface intensity measurements, Journal of Geophysical Research, vol.63, issue.31, pp.75-6339, 1970.
DOI : 10.1029/JA075i031p06339

A. Chulliat, E. Thébault, and G. Hulot, Core field acceleration pulse as a common cause of the 2003 and 2007 geomagnetic jerks, Geophysical Research Letters, vol.267, issue.7, pp.10-1029, 2010.
DOI : 10.1029/2009GL042019
URL : https://hal.archives-ouvertes.fr/hal-00540466

C. C. Finlay, M. Dumberry, A. Chulliat, and A. Pais, Short Timescale Core Dynamics: Theory??and??Observations, Space Science Reviews, vol.585, issue.1???2, pp.177-218, 2010.
DOI : 10.1007/s11214-010-9691-6

E. Friis-christensen, H. Lühr, and G. Hulot, Swarm: A constellation to study the Earth's magnetic field, Earth Planets Space, pp.351-358, 2006.

N. Gillet, D. Jault, E. Canet, and A. Fournier, Fast torsional waves and strong magnetic field within the Earth???s core, Nature, vol.58, issue.7294, pp.74-7710, 1038.
DOI : 10.1038/nature09010

R. Holme and J. Bloxham, The treatment of attitude errors in satellite geomagnetic data, Physics of the Earth and Planetary Interiors, vol.98, issue.3-4, pp.221-233, 1996.
DOI : 10.1016/S0031-9201(96)03189-5

J. R. Kan and L. C. Lee, Energy coupling function and solar wind-magnetosphere dynamo, Geophysical Research Letters, vol.81, issue.2, pp.577-580, 1979.
DOI : 10.1029/GL006i007p00577

A. Khokhlov, G. Hulot, and J. L. Mouël, On the Backus effect -I, Geophys, J. Int, vol.130, pp.701-703, 1997.
DOI : 10.1111/j.1365-246x.1997.tb01864.x

S. Kotsiaros, C. C. Finlay, and N. Olsen, Use of along-track magnetic field differences in lithospheric field modelling, Geophysical Journal International, vol.200, issue.2, pp.878-887, 2015.
DOI : 10.1093/gji/ggu431

M. Mandea, R. Holme, A. Pais, K. Pinheiro, A. Jackson et al., Geomagnetic Jerks: Rapid Core Field Variations and??Core Dynamics, Space Science Reviews, vol.267, issue.1, pp.147-175, 2010.
DOI : 10.1007/s11214-010-9663-x

S. Maus, Magnetic Field Model MF7, CIRES, Colo. [Available at www.geomag.us/models/MF7, 2010.
DOI : 10.1029/2006gc001521

P. T. Newell, T. Sotirelis, K. Liou, C. Meng, and F. J. Rich, A nearly universal solar wind-magnetosphere coupling function inferred from 10 magnetospheric state variables, Journal of Geophysical Research: Space Physics, vol.88, issue.A10, pp.120610-1029, 2007.
DOI : 10.1029/2005JA011257

N. Olsen, R. Haagmans, T. J. Sabaka, A. V. Kuvshinov, S. Maus et al., The Swarm End-To-End mission simulator study: Separation of the various contributions to Earth's magnetic field using synthetic data, Earth Planets Space, pp.359-370, 2006.

N. Olsen, The Swarm Satellite Constellation Application and Research Facility (SCARF) and Swarm data products, Earth, Planets and Space, pp.1189-1200, 2013.

N. Olsen, H. Lühr, C. C. Finlay, T. J. Sabaka, I. Michaelis et al., The CHAOS-4 geomagnetic field model, Geophysical Journal International, vol.197, issue.2, pp.815-827, 2014.
DOI : 10.1093/gji/ggu033

A. D. Richmond, Ionospheric Electrodynamics Using Magnetic Apex Coordinates., Journal of geomagnetism and geoelectricity, vol.47, issue.2, pp.191-212, 1995.
DOI : 10.5636/jgg.47.191

M. Rother, V. Lesur, and R. Schachtschneider, An algorithm for deriving core magnetic field models from the Swarm data set, Earth, Planets and Space, vol.169, issue.11, pp.1223-1231, 2013.
DOI : 10.5047/eps.2013.07.005

T. J. Sabaka, L. Tøffner-clausen, and N. Olsen, Use of the Comprehensive Inversion method for Swarm satellite data analysis, Use of the Comprehensive Inversion Method for Swarm satellite data analysis, pp.1201-1222, 2013.
DOI : 10.5047/eps.2013.09.007

T. J. Sabaka, N. Olsen, R. H. Tyler, and A. Kuvshinov, CM5, a pre-Swarm comprehensive geomagnetic field model derived from over 12 yr of CHAMP, Orsted, SAC-C and observatory data, Geophysical Journal International, vol.200, issue.3, pp.1596-1626, 2015.
DOI : 10.1093/gji/ggu493

L. Silva, L. Jackson, and J. Mound, Assessing the importance and expression of the 6 year geomagnetic oscillation, Journal of Geophysical Research: Solid Earth, vol.79, issue.199, pp.10-1029, 2012.
DOI : 10.1016/j.pepi.2012.03.002

D. P. Stern and J. H. Bredekamp, Error enhancement in geomagnetic models derived from scalar data, Journal of Geophysical Research, vol.63, issue.13, pp.1776-1782, 1975.
DOI : 10.1029/JA080i013p01776

E. Thébault, P. Vigneron, S. Maus, A. Chulliat, O. Sirol et al., Swarm SCARF Dedicated Lithospheric Field Inversion chain, Swarm SCARF Dedicated Lithospheric Field Inversion chain, pp.1257-1270, 2013.
DOI : 10.5047/eps.2013.07.008

P. Ultré-guérard, M. Hamoudi, and G. Hulot, Reducing the Backus Effect given some knowledge of the dip-equator, Geophysical Research Letters, vol.49, issue.16, pp.3201-320410, 1998.
DOI : 10.1029/98GL02211