Katika Kutafuta Maarifa:  Kitabu Cha II: Vioo na Mishumaa. - 2nd ed. - 

 - Nairobi   Oxford university Press  1961 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Reflection of light
<br/><br/><label>Dewey Class. No.: </label>535.323 KAT