Two similar Overton Books?

["sdale1uk" <stephendale@l...>]

I would be grateful if anyone could please tell me what the 
difference is between Overton's earlier work: "Burlington West, A 
Colonization History of the Burlington Railroad" and his later 
one: "Burlington Route: A History of Burlington Lines."

In particular, does his earlier book contain more corporate dates and 
details than the later book? I already have the later book; is there 
any point in getting the earlier work? Thank you.

Stephen Dale