Warning: file_get_contents(https://ojs.journalbusiness.my/ojs.php): failed to open stream: HTTP request failed! HTTP/1.1 404 Not Found in /var/www/ojs.unud.ac.id_backup/lib/pkp/includes/functions.inc.php on line 4 Malik Al Falah, Muhammad, Satya Kumara, I Nyoman, AND Ariastina, Wayan Gede. " PERKEMBANGAN RISET DAN PRODUK KOMERSIAL SISTEM PEMBERSIH PANEL SURYA" Jurnal SPEKTRUM [Online], Volume 8 Number 4 (8 January 2022)