قطار الجاذبية: الفرق بين النسختين

 

== المراجع ==

* Description of the concept [http://www.math.purdue.edu/~eremenko/train.html ''Gravity train''] and [http://www.math.purdue.edu/~eremenko/dvi/gravsol.pdf mathematical solution] (Alexandre Eremenko web page at Purdue University).

* Translations of the previous page into [http://www.azoft.com/people/seremina/edu/gravity_train-rom.html Romanian] and [http://www.pkwteile.de/wissen/projekt-pociag-gravity Polish].