In this note, we study the Seifert rational homology spheres with two complementary legs, that is, with a pair of invariants whose fractions add up to one. We give a complete classification of the Seifert manifolds with three exceptional fibers and two complementary legs that bound rational homology balls. The result translates into a statement on the sliceness of some Montesinos knots.
"Complementary Legs and Rational Balls." Michigan Math. J. 68 (3) 637 - 649, August 2019. https://doi.org/10.1307/mmj/1561708817