2.1 The Meaning of Meaning 37
for nitrous oxide using CML. The document-type definitions were highly
simplified in both cases. The simplified Medline document is figure 2.1. The
original Medline citation is to (Kuter 1999). The DTD being used is given
in figure 2.2. The nitrous oxide document is figure 2.3. The simplified CML
DTD being used is given in figure 1.6.
Figure 2.1 Example of part of a Medline citation using the Medline DTD.<!ELEMENT MedlineCitation
(MedlineID, PMID, DateCreated, ArticleTitle?)>
<!ATTLIST MedlineCitation
Owner CDATA "NLM"
Status (Incomplete|Completed) #REQUIRED>
<!ELEMENT MedlineID (#PCDATA)>
<!ELEMENT PMID (#PCDATA)>
<!ELEMENT DateCreated (Year, Month, Day)>
<!ELEMENT Year (#PCDATA)>
<!ELEMENT Month (#PCDATA)>
<!ELEMENT Day (#PCDATA)>
<!ELEMENT ArticleTitle (#PCDATA)>
Figure 2.2 Simplification of the Medline DTD.