In-text: Johannesburg Stock Exchange (2015) provided a comprehensive …., or, if at end of the sentence... The following are a list of companies …. (Johannesburg Stock Exchange, 2015).
Reference list: Johannesburg Stock Exchange. (2015). “Listed Companies”. Available from: <http://www.jse.co.za/current-companies/companies-and-financial-instruments>. [Accessed on 8 June 2015].