A proposed model No authors Acta Structilia · Volume 23, Issue 1 (2016) DOI: 10.18820/1023-0564/as2311.1 Abstract No abstract Article information Published1 January 2016 Languageen PublisherUniversity of the Free State LicenseNo license URL DOI10.18820/1023-0564/as2311.1 Journal ISSN1023-0564; 2415-0487