Armando, Y. G., A. T. Maryani, and M. Syarif. “The Effectiveness Of Providing Vulanic Ash (Tuff Vulcan) And Dolomite As Amelioran Materials On The Growth Of Immature Liberica Coffee Plants In Peat Land Of Mekar Jaya Village”. Jurnal Ilmiah Ilmu Terapan Universitas Jambi, vol. 4, no. 2, Dec. 2020, pp. 204-11, doi:10.22437/jiituj.v4i2.11608.