How to citations in the footnotes?

How you cite the footnotes in a document?

Example:

Diabetes: A public health problem

I began in 1998 to investigate the work of scientists searching for the genes that ‘cause’[1] type 2 diabetes…


[1] The terms _discove_r and _cause_ reference the usage by the scientists under investigation. This project will critically engage and show the consequences of the genetic determinism this usage implies (See Hubbard 1990; Hubbard and Wald 1993; Lewontin et al 1984).

Thank you,

Carla