. Tel, EMAIL: iyemori@kugi.kyoto-u.ac.jp INTERNET: http://wdc.kugi.kyoto-u.ac.jp WORLD DATA CENTRE FOR GEOMAGNETISM, MUMBAI Indian Institute of Geomagnetism Colaba EMAIL: abh@iigs.iigm.res, INTERNET: http://iigm.res.in References Alken P, Maus S, Chulliat A, Manoj C (2015) NOAA/NGDC candidate models for the 12th Generation International Geomagnetic Reference Field. Earth Planets Space, pp.606-850268, 2015.

D. Barraclough, International geomagnetic reference field: the fourth generation, Physics of the Earth and Planetary Interiors, vol.48, issue.3-4, pp.279-292, 1987.
DOI : 10.1016/0031-9201(87)90150-6

C. Barton, International Geomagnetic Reference Field: The Seventh Generation, Journal of geomagnetism and geoelectricity, vol.49, issue.2, pp.123-148, 1997.
DOI : 10.5636/jgg.49.123

A. Chulliat, G. Hulot, L. Newitt, C. Finlay, S. Maus et al., Magnetic flux expulsion from the core as a possible cause of the unusually large acceleration of the north magnetic pole during the 1990s B07101, doi:10 International Geomagnetic Reference Field: the eleventh generation, J Geophys Res. Geophys J Int, vol.115, issue.1833, pp.1216-1230, 1029.

C. Finlay, S. Maus, C. Beggan, M. Hamoudi, V. Lesur et al., Evaluation of candidate geomagnetic field models for IGRF-11, Earth, Planets and Space, vol.149, issue.10, pp.62787-804, 2010.
DOI : 10.5047/eps.2010.11.005

C. Finlay, N. Olsen, L. Tøffner-clausen, A. Fournier, J. Aubert et al., DTU candidate field models for IGRF-12 and the CHAOS-5 geomagnetic field model. Earth Planets Space A candidate secular variation model for IGRF-12 based on Swarm data and inverse geodynamo modelling, Earth Planets and Space, vol.67, p.81, 2015.

N. Gillet, O. Barrois, and C. Finlay, Stochastic forecasting of the geomagnetic field from the COV-OBS.x1 geomagnetic field model and candidate models for IGRF-12. Earth, Planets and Space, p.71, 2015.

B. Hamilton, V. Ridley, C. Beggan, and S. Macmillan, The BGS magnetic field candidate models for the 12th generation IGRF. Earth, Planets and Space, pp.69-79, 2015.

M. Hamoudi, E. Thébault, V. Lesur, and M. Mandea, GeoForschungsZentrum Anomaly Magnetic Map (GAMMA): A candidate model for the World Digital Magnetic Anomaly Map, Geochemistry, Geophysics, Geosystems, vol.13, issue.3, 2007.
DOI : 10.1029/2007GC001638

K. Hemant, E. Thébault, M. Mandea, D. Ravat, and S. Maus, Magnetic anomaly map of the world: merging satellite, airborne, marine and ground-based magnetic data sets, Earth and Planetary Science Letters, vol.260, issue.1-2, pp.56-71, 2007.
DOI : 10.1016/j.epsl.2007.05.040
URL : https://hal.archives-ouvertes.fr/hal-00311479

G. Hulot, N. Olsen, and T. Sabaka, The present field, geomagnetism, Treatise on Geophysics, pp.33-75, 2007.

R. Langel and R. Estes, A geomagnetic field spectrum, Geophysical Research Letters, vol.23, issue.4, pp.250-253, 1982.
DOI : 10.1029/GL009i004p00250
URL : http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.545.4483

R. Langel, D. Barraclough, D. Kerridge, V. Golovkov, T. Sabaka et al., Definitive IGRF models for 1945, 1950, 1955, and 1960., Journal of geomagnetism and geoelectricity, vol.40, issue.6, pp.645-702, 1950.
DOI : 10.5636/jgg.40.645

R. Langel, International Geomagnetic Reference Field: The Sixth Generation., Journal of geomagnetism and geoelectricity, vol.44, issue.9, pp.679-707, 1992.
DOI : 10.5636/jgg.44.679

J. Léger, T. Jager, F. Bertrand, G. Hulot, L. Brocco et al., In-flight performance of the Absolute Scalar Magnetometer vector mode on board the Swarm satellites, Earth, Planets and Space, vol.1, issue.5, p.67, 2015.
DOI : 10.1186/s40623-015-0231-1

V. Lesur, M. Rother, I. Wardinski, R. Schachtschneider, M. Hamoudi et al., Parent magnetic field models for the IGRF-12 GFZ-candidates. Earth Planets Space, in press Lowes FJ (2000) An estimate of the errors of the IGRF, Earth Planets Space, vol.52, issue.12, pp.1207-1211, 1945.
DOI : 10.1186/s40623-015-0239-6
URL : https://hal.archives-ouvertes.fr/hal-01199678

S. Macmillan, S. Maus, T. Bondar, A. Chambodut, V. Golovkov et al., The 9th Generation International Geomagnetic Reference Field, Earth, Planets and Space, vol.52, issue.12, pp.1051-1056, 2003.
DOI : 10.1186/BF03351778
URL : https://hal.archives-ouvertes.fr/hal-00119021

M. Mandea and S. Macmillan, International Geomagnetic Reference Field???the eighth generation, Earth, Planets and Space, vol.72, issue.12, pp.1119-1124, 2000.
DOI : 10.1186/BF03352342
URL : http://doi.org/10.1186/bf03352342

S. Maus, S. Macmillan, T. Chernova, S. Choi, D. Dater et al., The 10th-generation International Geomagnetic Reference Field, Geophys J Int, vol.161, pp.561-565, 2005.
DOI : 10.1016/j.pepi.2005.03.006
URL : http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.380.2035

S. Maus, T. Sazonova, K. Hemant, J. Fairhead, D. Ravat et al., National geophysical data center candidate for the world digital magnetic anomaly map):Q06017. doi:10 Ørsted satellite captures high-precision geomagnetic field data, Geochem Geophys Geosyst EOS. Trans Am. Geophys Un, vol.8, issue.82, p.81, 1029.
DOI : 10.1029/2007gc001643

N. Peddie, International geomagnetic reference field: The third generation., Journal of geomagnetism and geoelectricity, vol.34, issue.6, pp.309-326, 1982.
DOI : 10.5636/jgg.34.309

C. Reigber, H. Lühr, and P. Schwintzer, CHAMP mission status, Advances in Space Research, vol.30, issue.2, pp.129-134, 2002.
DOI : 10.1016/S0273-1177(02)00276-4

D. Saturnino, F. Civet, B. Langlais, E. Thébault, M. Mandea et al., Main field and secular variation candidate models for the 12th IGRF generation after 10 months of Swarm measurements, Earth, Planets and Space Evaluation of candidate geomagnetic field models for IGRF-12 A 2015 International Geomagnetic Reference Field (IGRF) candidate model based on Swarm's experimental absolute magnetometer vector mode data, Earth Planets Space Earth Planets Space Earth Planets Space, vol.52, pp.1227-1233, 2000.

A. Zmuda, The International Geomagnetic Reference Field: introduction, Bull Int Assoc Geomag Aeronomy, vol.28, pp.148-152, 1971.