\Bibitem{Mar77} \by G.~A.~Margulis \paper Cobounded subgroups of algebraic groups over local fields \jour Funktsional. Anal. i Prilozhen. \yr 1977 \vol 11 \issue 2 \pages 45--57 \mathnet{http://mi.mathnet.ru/faa2067} \mathscinet{http://mathscinet.ams.org/mathscinet-getitem?mr=442107} \zmath{https://zbmath.org/?q=an:0348.22005|0412.22007} \transl \jour Funct. Anal. Appl. \yr 1977 \vol 11 \issue 2 \pages 119--128 \crossref{https://doi.org/10.1007/BF01081890}