diff --git a/2019-01-07.md b/2019-01-07.md
index fab9708..ae5a5f1 100644
--- a/2019-01-07.md
+++ b/2019-01-07.md
@@ -118,11 +118,14 @@ Four-terminal devices with a bulk connection require the concept of global nets.
 global net represents the bulk (p-body) of the wafer. n-type transistors will have their bulk terminal
 connected to this virtual net. Such a net is represented by a global net. Global nets are inherited by
 parent circuits automatically. Global nets can be included in a connectivity specification with 
-"connect_global". A MOS4 device extractor emits bulk terminal shapes as copies of the gate shape to
-a specified layer. When connecting this layer to the global "BULK" net, the B terminal of the 
+"connect_global". 
+
+A MOS4 device extractor emits bulk terminal shapes as copies of the gate shape to
+a layer as "W" input (well). When connecting this layer to the global "BULK" net, the "B" (bulk) terminal of the 
 MOS4 devices will be connected to this global net.
 
-Here is code for such an extraction. It also recognizes tie-down diodes for substrate and well connections:
+Here is code for such an extraction. It also recognizes tie-down diodes for substrate and well connections. The p-tie-down diode will also connect to the "BULK" global net. The n diode will connect to the n-well area. n-well is 
+included in the net extraction like a conductive layer.
 
 ```ruby
  ly = RBA::Layout::new