Speck, Heinrich. "Soils of the Mount Kenya Area: Their formation, ecology, and agricultural significance". Mountain Research and Development. International Mountain Society. 2 (2). 1982: 201–221. doi:10.2307/3672965. JSTOR3672965.
Ojany, Francis. "Mount Kenya and its Environs: A review of the interaction between mountain and people in an equatorial setting". Mountain Research and Development. International Mountain Society. 13 (3). avqust 1993: 305–309. doi:10.2307/3673659. JSTOR3673659.
Speck, Heinrich. "Soils of the Mount Kenya Area: Their formation, ecology, and agricultural significance". Mountain Research and Development. International Mountain Society. 2 (2). 1982: 201–221. doi:10.2307/3672965. JSTOR3672965.
Ojany, Francis. "Mount Kenya and its Environs: A review of the interaction between mountain and people in an equatorial setting". Mountain Research and Development. International Mountain Society. 13 (3). avqust 1993: 305–309. doi:10.2307/3673659. JSTOR3673659.