1. 1) Japan TAPPI:“Recycled paper”, in “Dictionary of Pulp and Paper, the Revised Sixth Edition”, Japan TAPPI, Tokyo, p. 107 (2014).
2. 2) Nomura, T.:“Recycled paper”, in “Printing Paper to be Used with Good Care”, Japan Printing News, Co., Ltd., Tokyo, p. 42-43 (1993).
3. 3) Komiya, H.:“Paper began as recycled fiber”, in “A Comprehensive Book on Paper”, Nikkan Kogyo Shimbun Ltd., Tokyo, p. 72 (2001).
4. 4) Hara, H.:“Wastepaper and recycled paper”, in “The Paper Story, the Revised Edition”, Japanese Standards Association, Tokyo, p. 136-149 (2002).
5. 5) Ministry of the Environment:“Basic Policy on Promoting Green Procurement (Provisional Translation)”, p. 8-16 (2022), https://www.env.go.jp/en/laws/policy/green/h31bp_en.pdf.