Abdul Kalam A.P.J & Singh, S. P. Target 3 billion: PURA:innovative solutions towards sustainable development. Penguin books.
Παραπομπή Chicago StyleAbdul Kalam A.P.J και Srijan Pal Singh. Target 3 Billion: PURA:innovative Solutions Towards Sustainable Development. 2011: Penguin books.
Παραπομπή MLAAbdul Kalam A.P.J και Srijan Pal Singh. Target 3 Billion: PURA:innovative Solutions Towards Sustainable Development. Penguin books.
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