sentences:  Pascual Jordan, motivated by questions in quantum logic, initiated a study of "noncommutative lattices" in his 1949 paper, "Über Nichtkommutative Verbände", choosing the absorption identities
  
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  He referred to those algebras satisfying them as "Schrägverbände".By varying or augmenting these identities, Jordan and others obtained a number of varieties of noncommutative lattices.Beginning with Jonathan Leech's 1989 paper, "Skew lattices in rings", skew lattices as defined above have been the primary objects of study.