PMID (PubMed ID) is the unique identifier for a publication's abstract in PubMed.
PMCID (PubMed Central ID) is the unique identifier for a free complete article (once it is publicly available) in PubMed Central.
PubMed and PubMed Central, produced by the U.S. National Library of Medicine, are text archives of biomedical and life sciences literature.
A DOI (Digital Object Identifier) is a publisher’s unique identifier for a publication. The prefix http://dx.doi.org/ is presumed. Publishers may charge for access.
Pearson G, Moon CW.Bridging Two Biomedical Journal Databases with XML - A Case Study. Proc. 14th IEEE Symposium on Computer-Based Medical Systems: IEEE Computer Society. 2001 Jul;:309-14.
Kayaalp M, Aronson AR, Humphrey SM, Ide NC, Tanabe LK, Smith LH, Demner-Fushman D, Loane RF, Mork JG, Bodenreider O.Methods for accurate retrieval of MEDLINE citations in functional genomics. The Twelfth Text Retrieval Conference (TREC 2003). 2003:441-50.
Fan Y, Hwang K, Gill M, Huang HK.Some Connectivity and Security Issues of NGI in Medical Imaging Applications Journal of High Speed Networks. 2000;9: 3-13.
Kim I, Chien SI.Selectively attentive learning of multilayer perceptron for fast speaker adaptation. Proc. Int’l. Conf. Artificial Intelligence (ICAI'2000), vol.3, pp. 1259-1264, Las Vegas, June 2000.