l. Kathy Sierra, 'OCA / OCP Java SE 7 Programmer 1 & 11 study Guide, Chapter 1, 2 and 7...
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l. Kathy Sierra, 'OCA / OCP Java SE 7 Programmer 1 & 11 study Guide, Chapter 1, 2 and 7 Oracle press (2014) Reference Books: l. Khalid A Mughal, 'A programmer's guide to Java SE 8