M. Ekiel-Jeżewska and E. Wajnryb, “Three-particle motion under gravity in Stokes flow: an equilibrium for spheres in contrast to ‘an end-of-world’ for point particles”, Arch. Mech., vol. 58, no. 4-5, pp. 489–494, Sep. 2006, Accessed: Dec. 13, 2025. [Online]. Available: https://am.ippt.pan.pl/index.php/am/article/view/v58p489