If there is more than one author, the citation might look like this (Kusnick and Waterstraat, 1996) or like this (Kusnick and others, 1995). If you use a reference more than once, you just insert the ...

Based on: Eleventh Annual Report of the Trustees and Superintendent of the Northampton (Mass.) Lunatic Hospital. Select the format you want to export the citation of this publication.