Tahun tropis: Perbedaan antara revisi

* Astronomical Applications Dept. of [[United States Naval Observatory]]. (2009). ''Multiyear Interactive Computer Almanac'' (ver. 2.2). Richmond VA: Willman-Bell.

* Blackburn, B. & Holford-Strevens, L. (2003, corrected reprint of 1999). ''The Oxford companion to the year''. Oxford University Press.

* Borkowski, K. M. [http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1991JRASC..85..121B&data_type=PDF_HIGH&whole_paper=YES&type=PRINTER&filetype=.pdf The tropical year and the solar calendar]. (1991). ''Journal of the Royal Astronomical Society of Canada, 85''(3), 121–130.

* [[Bureau International des Poids et Mesures]]. (2006). [http://www.bipm.org/en/si/si_brochure/general.html ''The International System of Units''.] author.

* Butrica, A. J. (1996) [http://history.nasa.gov/SP-4218/sp4218.htm ''NASA SP-4218: To See the Unseen - A History of Planetary Radar Astronomy''.] NASA.

* Dershowitz, N. & [[Edward M. Reingold|Reingold, E.M.]] (2008). ''Calendrical Calculations'' (3rd ed.). Cambridge University Press. ISBN 978-0-521-70238-6

* [[International Earth Rotation Service]] (2010, January 28). [http://maia.usno.navy.mil/ser7/ser7.dat ''Bulletin A 23''(4)]. author.

* [[Jet Propulsion Laboratory]]. (2005). [http://deepspace.jpl.nasa.gov/dsn/history/index.html ''DSN: History'']. author.

* Laskar, J. (1986). [http://adsabs.harvard.edu/abs/1986A%26A...157...59L Secular terms of the classical planetary theories using the results of general theory]. ''Astronomy and Astrophysics'', 157, 59–70. ISSN 0004-6361.

* [[Dennis McCarthy (scientist)| McCarthy, D. D.]] & Seidelmann, P. K. (2009). ''Time from Earth rotation to atomic physics''. Weinhein: Wiley-VCH Verlag GmbH & Co. KGaA.

* [[Jean Meeus|Meeus, J.]] & Savoie, D. (1992). [http://adsabs.harvard.edu/abs/1992JBAA..102...40M The history of the tropical year]. ''Journal of the British Astronomical Association'', 102(1), 40–42.

* Morrison, L. V. & Stephenson, F. R. (2004). [http://adsabs.harvard.edu/abs/2004JHA....35..327M Historical values of the Earth's clock error ΔT and the calculation of eclipses]. ''Journal for the History of Astronomy'' Vol. 35, Part 3, No. 120, p. 327–336

* Newcomb, S. (1898). ''Tables of the four inner planets'' (Vol. 6) in ''Astronomical papers prepared for the use of the American ephemeris and nautical almanac'' (2nd ed.). Washington: Bureau of Equipment, Navy Dept.

* North, J. D. (1983). The Western calendar - "Intolerabilis, horribilis, et derisibilis"; four centuries of discontent. In [[George Coyne| G. V. Coyne]], M. A. Hoskin, & O. Pedersen (Eds.). ''Gregorian reform of the calendar''. Vatican Observatory.

* Seidelmann, P. K. (Ed.). (1992). ''Explanatory supplement to the Astronomical almanac''. Sausalito, CA: University Science Books. ISBN 0-935702-68-7

* tropic. (1992). ''American Heritage Dictionary'', 3rd ed. Boston: Houghton-Mifflin.

[[CategoryKategori:Kalender]]