http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
... sub-excavating, timbering and the construction of the brickwork of tunnels
This title explains in detail the setting out of the works, shaft sinking, and heading driving, ranging the lines, and levelling under ground, sub-excavating, timbering and brickwork construction of tunnels, with additional chapters relating to the St Gothard and Mont Cenis tunnels.