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<Paper uid="P83-1006">
  <Title>A Modal Temporal Logic for Reasoning about Change</Title>
  <Section position="1" start_page="0" end_page="0" type="abstr">
    <SectionTitle>
ABSTRACT
</SectionTitle>
    <Paragraph position="0"> We examine several behaviors for query systems that become possible with the ability to represent and reason about change in data bases: queries about possible futures, queries about alternative histories, and offers of monitors as responses to queries. A modal temporal logic is developed for this purpose. A completion axiom for history is given and modelling strategies are given by example.</Paragraph>
  </Section>
class="xml-element"></Paper>