Malaysia was a landmass on Earth that Polly Wright recognised. Thus, when she saw Mondas for the first time, she was able to pick out a region of that globe that looked like Malaysia. (TV: The Tenth Planet)
In 2009 John Benton was invited to Sarah Jane Smith's aborted wedding with Peter Dalton, but couldn't make it because he was doing something secret out in Malaysia. (PROSE: The Wedding of Sarah Jane Smith)