Wasmi Osman Luhaib, S., & Khalid Khaleel Mohammed, D. (2012). Design of Delta-Sigma ΣΔ based Fractional N PLL Frequency Synthesizer for GSM Mobile Systems. Al-Rafidain Engineering Journal (AREJ), 20(3), 26–34. https://doi.org/10.33899/rengj.2012.50474