D. S. Manurung, Y. Hasanah, and R. Sipayung, “Growth Response and Production of Soybean (Glyicine max (L.) on Application of Phosphorous Fertilizer and Rhizobium Inoculation”, Indonesian J. Agric. Res, vol. 1, no. 3, pp. 289 - 294, Feb. 2019.