Thread.Sleep () в переносимой библиотеке классов

Документы MSDN говорят, что Thread.Sleep () можно использовать в переносимой библиотеке классов. Компилятор говорит иначе. Какие у меня есть альтернативы, кроме спин-петли? Thread.CurrentThread.Join () тоже не существует.

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