Brustad, Kristen, author
Georgetown University Press, 1995
Buku Teks
Sekolah Tinggi Agama Islam Negeri (STAIN) Tulungagung,
Majalah, Jurnal, Buletin
Ross, Alf, author
Longmans, Green , 1947
Buku Teks
Fawcett, Joe, author
John Wiley & Sons, 2012
Buku Teks
Fraser, Barry J., editor
Springer, 2012
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