Integration of technologies : biogas production, fertilizer production and biogas upgradingSokk, Olev; Loigu, Enn; Kuusik, Rein, keemik; Menert, Anne12th World Congress on Anaerobic Digestion : October 31st - November 4th, 2010, Guadalajara, Jalisco, Mexico2010 / [6] p : ill https://www.sei.org/wp-content/uploads/2018/02/4367.pdf

Integration of technologies : biogas production, fertilizer production and biogas upgradingSokk, Olev; Loigu, Enn; Kuusik, Rein, keemik; Menert, Anne12th World Congress on Anaerobic Digestion : October 31st - November 4th, 2010, Guadalajara, Jalisco, Mexico2010 / p. 179 https://www.sei.org/publications/integration-of-technologies-biogas-production-fertilizer-production-and-biogas-upgrading/