Cite in two different ways in same paper? Can I cite in two different ways in the same paper? Is this considered appropiate?

Example.


  It was first shown in Heston (1949) that the model is complete. An easier proof can be found in [5].
You should stick to one citation style in one document. But mentioning author names or publication dates in the text while using a numbered citation style is no problem: 


  It was first shown by Heston in 1949 that the model is complete [4]. An easier proof can be found in [5].