Effect of hill spacing on radish yield at royal university of agriculture's crop station,(ឥទ្ធិពលចន្លោះគុម្ពទៅលើទិន្នផលដំណាំឆៃដាវនៅស្ថានីយ៍សាកលវិទ្យាល័យភូមិន្ទកសិកម្ម) HEANG SOPHAL AGR HEA 2004 B029 Or.1 phnom penh RUA 2004 2004 Text 43p. https://drive.google.com/file/d/10fa7SoOaZqsitGV8DIVBf7r2QeTYCvy8/view?usp=sharing