Sheaves on Graphs, Their Homological Invariants, and a Proof ...
Joel Friedman
[Fri03] [Fri06] [Fri07] [Fri08] [Fri11a] [Fri11b] [Fri11c] [FT05] [Ger83] [GM03] [Gro77 ] [Har77] [Har92] [How54] [HS97] [Imr77a] [Imr77b] [Iva99] [Iva01] [JKM03] Joel Friedman, Relative expanders or weakly relatively Ramanujan graphs, Duke Math ...