On the competition graphs of $d$-partial orders
  In this paper, we study the competition graphs of $d$-partial orders and obtain their characterization which extends results given by Cho and Kim \cite{chokim} in 2005. We also show that any graph can be made into the competition graph of a $d$-partial order for some positive integer $d$ as long as adding isolated vertices is allowed. We then introduce the notion of the partial order competition dimension of a graph and study graphs whose partial order competition dimensions are at most three. 
Jihoon Choi, Kyeong Seok Kim, Suh-Ryung Kim, Jung Yeun Lee, Yoshio   Sano
math.CO