Silapanuntakul, Suthep, Intrarasaksit, Prat, Vatanasomboon, Pisit, AND Tantrakarnapa, Kraichat. " Uptake of Copper and Zinc in Lettuce (Lactuca sativa L.) Planted in Sida Soil and Lignite Bottom Ash Mixtures" Naresuan University Journal: Science and Technology (NUJST) [Online], Volume 25 Number 3 (17 July 2017)