Tunggul Ismail, A., I. Ismail, and R. Abdu Rahman. “Increasing the Reliability of Biomass Solid Fuel Combustion Using a Combined Regenerative Heat Exchanger As an Indirect Burner”. Eastern-European Journal of Enterprise Technologies, vol. 5, no. 8(119), Oct. 2022, pp. 53-61, doi:10.15587/1729-4061.2022.265803.