|
GB740468A
|
|
Improvements in and relating to drilling in rock and other hard substances
|
|
US2756967A
|
|
Rock-drill
|
|
GB720489A
|
|
Improvements in or relating to rock drill bits
|
|
GB680950A
|
|
Improvements in cutting devices for mounting on a chain in cutting machines
|
|
GB686185A
|
|
Improvements in and relating to rotary boring machines
|
|
DE806845C
|
|
Tools, especially chisels for cutting machines, with dissolved hard metal insert
|
|
GB423647A
|
|
Improvements in stone boring tools, rock drills, and the like
|
