Pesticide Residue Measurement in Commonly Used Vegetables Using the QuEChERS Method, AlSaikhan, Waad Hamad, Almatroodi Saleh A., Almatroudi Ahmad, Alsahli Mohammed A., and Rahmani Arshad Husain , Pharmacognosy Journal, January 2021, Volume 13, Issue 1, p.142-149, (2021)