Lubis AIU. Study Of The Effectiveness Of The Use Of Gypsum And Volcanic Ash On Stability Of The Clay Soil Based On The CBR Value And The Unconfined Compression Test. Mekintek [Internet]. 2021 Oct. 30 [cited 2026 Jul. 3];12(2):37-45. Available from: https://ejournal.isha.or.id/index.php/Mekintek/article/view/26