Drilling unit model БУ-75, Operating instructions
английский/Drilling unit model БУ-75 : Operating instructions / V/o "Machinoexport".Drilling unit model БУ-75 : Operating instructions / V/o "Machinoexport".Drilling unit model БУ-75 : Operating instructions.Μ./Vneshtorgizdat/, [1960] ( ). - Vneshtorgizdat, [1960]. - 3 т. : черт. ; 29 см см.Drilling unit model БУ-75 : Operating instructions. Μ., [1960] .Тг-1068/1218/"Machinoexport", v/o /