8CHOI S, KIM H, YOON J, et al. An SAO-based text-mining approach for technology roadmapping using patent information[J]. R & D Management, 2013,43(1):52-74.
9CHENG T, WANG M.The patent-classification technology/function matrix - a systematic method for design around[J]. Journal of lnteUectual Property Rights, 2013,18(3):158-167.
10LIU K, YEN Y. A quick approach to get a technology-function matrix for an interested technical topic of patents[J]. International Journal of Arts and Commerce, 2013,2(6):85-96.