Joel Glazer, United's co-chairman, issued a "voluntary free-payment notice" on Monday informing lenders that Red Football Joint Venture Ltd.

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College, on the other hand, is voluntary and requires payment by the individual.

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Indeed PayPal is a private corporation and using their payment service is voluntary.

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But we are also opening the health service to private and voluntary-sector partnerships, introducing a payment-by-results system, creating competition and allowing hospitals to become self-governing trusts.

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In return, under a voluntary contract, the farmer would receive a small annual payment or wage.

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The government is also switching increasingly to a "payment by results" method of working, whereby voluntary agencies are paid only if they are successful in cutting reoffending.

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Earlier, Mr Grayling was questioned about his plans to overhaul the probation service with a payment-by-results model of provision involving private firms and voluntary groups.

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