Correction to "Looking into a Node"

There was an error in the Spring 2014 "Circuit Intuitions" column titled "Looking into a Node" [ibid., vol 6, no. 2, pp. 8??10, 2014]. In Figure 3 of the article (a corrected figure is given here), we were interested in finding vd1 and vout in a cascade configuration. We did this by first finding an expression for vd1. In the original article, the final expression for vd1 has an extra ro1 factor, which is now corrected here.