Van Ech, Jacobus Adrianus. <br/><br/>
A system of temporally relative medal and deontic predicate logic and its philosophical applications. 
 A system of temporally relative medal and deontic predicate ... 

<br/><br/>Thesis (Ph.D.)--University of Groningen, 1981. 
<br/><br/>Includes bibliographical references. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Deontic logic.<br/>Logic, Symbolic and mathematical.<br/>Semantics (Philosophy)