Funding for this research was provided by:
Ministerio de Economía y Competitividad (FEDER-MTM2016-78647-P grant)
African Centre of Excellence in Mathematical Sciences and Applications
Article History
Received: 14 February 2018
Accepted: 11 June 2018
First Online: 26 June 2018
Change Date: 1 November 2018
Change Type: Correction
Change Details: There is a mistake in the last subsection (5.3 Totally geodesic null hypersurfaces in Robertson–Walker spaces) of the paper [1]