Northern Pacific Engineering Drawing: Depot at Helena, Montana, prepared in 1964. Burlington Northern File Number 4616, Reference Number 10112, Sheet 001.

Northern Pacific Engineering Drawing: Depot at Helena, Montana, prepared in 1970. Burlington Northern File Number 4616, Reference Number 10103, Sheet 002.

Northern Pacific Engineering Drawing: Depot at Helena, Montana, prepared in 1970. Burlington Northern File Number 4616, Reference Number 10103, Sheet 001.

Northern Pacific Engineering Drawing: Depot at Helena, Montana, undated. Burlington Northern File Number 4616, Reference Number 101.

Northern Pacific Engineering Drawing: Depot at Helena, Montana, undated. Burlington Northern File Number 4616, Reference Number 101, Sheet A-1.

Northern Pacific Engineering Drawing: Depot at Helena, Montana, undated. Burlington Northern File Number 4616, Reference Number 101, Sheet 001.

Northern Pacific Engineering Drawing: Diesel Fueling Facilities at Helena, Montana, prepared in 1953. Burlington Northern File Number 1271-1, Reference Number 10103, Sheet 001.

Northern Pacific Engineering Drawing: Diesel Fueling Facilities at Helena, Montana, prepared in 1953. Burlington Northern File Number 1271-2, Reference Number 10103, Sheet 002.

Northern Pacific Engineering Drawing: Diesel Fueling Facilities at Helena, Montana, prepared in 1953. Burlington Northern File Number 1271-3, Reference Number 10103, Sheet 003.

Northern Pacific Engineering Drawing: Diesel Fueling Facilities at Helena, Montana, prepared in 1957. Burlington Northern File Number 1271-4, Reference Number 10102, Sheet 004.