Product Development Using Bio-mimicry Design Spiral Approach of Swimming AidPurwaningsih Ratna, Rahardjo Danu, Budiawan Wiwik, Adi Wicaksono Purnawan and Santosa HaryoE3S Web Conf., 73 (2018) 08007DOI: https://doi.org/10.1051/e3sconf/20187308007
