https://torontodawah.com/when-reciting-the-duaa-for-istikhaarah-does-one-have-to-utter-the-affair-with-the-tongue-or-can-one-merely-recall-it-in-the-heart-ibn-hajr-al-asqalaani/
When Reciting The Du'aa For Istikhaarah, Does One Have To Utter The Affair With The Tongue Or Can One Merely Recall It In The Heart - Ibn Hajr Al-Asqalaani