Media type: E-Article Title: The algebraic behaviour of the weyl tensor in the geometrical optics approximation Contributor: Marcello Anile, Angelo Published: Springer Science and Business Media LLC, 1976 Published in: Annali di Matematica Pura ed Applicata, 109 (1976) 1, Seite 357-369 Language: English DOI: 10.1007/bf02416968 ISSN: 0373-3114; 1618-1891 Keywords: Applied Mathematics Origination: Footnote: