Before revision: "VLSI technology: fundamentals and applications", by Yasuo Tarui, 1986, ISBN 3540125582, Chapter 4: "Mask Inspection Technology"
After revision: Modern technologies for locating defects in photomasks involve scanning electron microscopy and other advanced tools."VLSI technology: fundamentals and applications", by Yasuo Tarui, 1986, ISBN 3540125582, Chapter 4: "Mask Inspection Technology"