Keabsahan Emoji Jempol Sebagai Ṣīgah Akad Jual Beli Online di Indonesia Berdasarkan Kaidah al-‘Ādah Muḥakkamah: The Validity of the Thumbs-Up Emoji as the Ṣīghah of an Online Sale and Purchase Contract in Indonesia Based on the Maxim al-‘Ādah Muḥakkamah. AL-FIKRAH: Jurnal Kajian Islam, v. 3, n. 6, p. 1098–1103, 5 Nov.2026.