Optimization of chitosan and sodium carboxymethylcellulose as mucoadhesive system in theophylline tablet - Irawan, Eka Deddy; Faculty of Pharmacy, Universitas Jember; Jalan Kalimantan I/2 Jember 68121 (Faculty of Pharmacy Universitas Gadjah Mada, Yogyakarta, Skip Utara, 55281, Indonesia, 2011)