Figure 4B.4. On the left is a current source. The arrow inside the circle is pointing down indicating the direction of current flow. It is labeled GmVgk. In parallel with the current source is a resistor labeled rp. The R is lower case. There are terminals at the top and bottom of the resistor. To the right there is another resistor connected to the terminals. It is labeled Rb with a capitol R. connected in parallel with Rb is another resistor labeled Rcf. To clarify, all three resistors are connected in parallel. End verbal description.