GB/T 18024.2-2010 Graphical symbols for technical documents of coal mine machinery Part 2: Graphical symbols for supports and pillars of coal mining face (English Version)
2011GB/T 18024.2-2010 Graphical symbols for technical documents of coal mine machinery Part 2: Graphical symbols for supports and pillars of coal mining face
2000GB/T 18024.2-2000 Graphical symbols for use in technical documentation of coal mine machinery-Graphical symbols for coal face support machinery