"It's really important that we change our mindset from dependence on one source of energy to many different complementary sources, " Evans said.

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Selling branded toys and merchandise based on its very popular titles could open up an additional source of revenue, and help Zynga reduce its dependence on Facebook.

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In fact, over the past three years Deutsche Bank has deliberately and dramatically reduced its dependence on risk-taking as a source of operating earnings, while enjoying more substantial progress with clients than at any time in its recent history.

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