You can search for any reference by title, author, date, editor, journal and publisher. Searching is case insensitive, and allows for only partial terms (e.g. seq with pickup both RNA-Seq and sequencing) matching. You can also use advanced queries that are detailed here.
Orr and Chen (2002) "Aging and neural control of the GI tract: IV. Clinical and physiological aspects of gastrointestinal motility and aging." Am. J. Physiol. Gastrointest. Liver Physiol. 283(6):G1226-G1231 (PubMed)