Holmgren, D. (2002). Permaculture: Principles and pathways beyond sustainability. Holmgren design services.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रHolmgren, David. Permaculture: Principles and Pathways Beyond Sustainability. Victoria: Holmgren design services, 2002.
एमएलए (9वां संस्करण) प्रशस्ति पत्रHolmgren, David. Permaculture: Principles and Pathways Beyond Sustainability. Holmgren design services, 2002.
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