Northern Pacific Engineering Drawing: Piping Plans, Mullan Tunnel, Blossburg, Montana, Line Segment 042, Milepost 19.6, undated.

Northern Pacific Engineering Drawing: Plan of Layout, Mullan Tunnel, Blossburg, Montana, Line Segment 042, Milepost 19.6, undated.

Northern Pacific Engineering Drawing: Proposed Blower and Ventilating, Mullan Tunnel, Blossburg, Montana, Line Segment 042, Milepost 19.6. Sheet 1267 - 3, undated.

Northern Pacific Engineering Drawing: Proposed Change Pipe, Mullan Tunnel, Blossburg, Montana, Line Segment 042, Milepost 19.6. Sheet 282 - 46, undated.

Northern Pacific Engineering Drawing: Proposed Concrete Work North, Mullan Tunnel, Blossburg, Montana, Line Segment 042, Milepost 19.6. Sheet 1267 - 3, undated.

Northern Pacific Engineering Drawing: Proposed Concrete Work South, Mullan Tunnel, Blossburg, Montana, Line Segment 042, Milepost 19.6. Sheet 1267 - 3, undated.

Northern Pacific Engineering Drawing: Proposed Connection Nozzle, Mullan Tunnel, Blossburg, Montana, Line Segment 042, Milepost 19.6, undated.

Northern Pacific Engineering Drawing: Proposed Rib Sections, Nimrod Tunnel, west of Nimrod, Montana, Line Segment 042, Milepost 90.8. Sheet 81329, undated.

Northern Pacific Engineering Drawing: Proposed Tunnel Liner, Tunnel Liner near Reservation, Tacoma, Washington, Line Segment 051, Milepost 37.56. Sheet 2019 - 2, undated.

Northern Pacific Engineering Drawing: Proposed Ventilating Nozzle Change, Mullan Tunnel, Blossburg, Montana, Line Segment 042, Milepost 19.6. Sheet 1267 - 3, undated.