They have even developed their own instruction manuals, such as the publication Apply Yourself to Reading and Writing, which has been produced in 28 languages.
حتى انهم ألّفوا كتبهم التعليمية الخاصة ،‏ مثل مطبوعة واظِبوا على القراءَة والكتابة التي صدرت بـ‍ ٢٨ لغة .‏