  This paper deals with a universal coding problem for a certain kind of
multiterminal source coding system that we call the complementary delivery
coding system. In this system, messages from two correlated sources are jointly
encoded, and each decoder has access to one of the two messages to enable it to
reproduce the other message. Both fixed-to-fixed length and fixed-to-variable
length lossless coding schemes are considered. Explicit constructions of
universal codes and bounds of the error probabilities are clarified via
type-theoretical and graph-theoretical analyses. [[Keywords]] multiterminal
source coding, complementary delivery, universal coding, types of sequences,
bipartite graphs
