Computing Connected Components on Parallel Computers
We present a parallel algorithm which uses n2 processors to find the connected
components of an undirected graph with n vertices in time O(log2n).  An
O(log2n) time bound also can be achieved using only n$n/$log2n)) processors.
The algorithm can be used to find the transitive closure
of a symmetric Boolean matrix.  We assume that the processors have
access to a common memory.  Simultaneous access to the same location
is permitted for fetch instructions but not for store instructions.
CACM August, 1979
Hirschberg, D.S.
Chandra, A.K.
Sarwate, D.V.
