Books and articles used while writing articles at this web page.
Listed also as worth reading for everyone interested in Mobile Telecom Networks:
[1] R. Kreher, T. Rüdebush: "UMTS Signaling. UMTS Interfaces, Protocols, Message Flows and Procedures Analyzed and Explained" 2nd Edition, John Wiley & Sons Ltd. 2007
[2] J. Kołakowski, J.Cichocki: "UMTS System Telefonii Komórkowej Trzeciej Generacji" Wydanie 2 zmienione, Wydawnictwo Komunikacji i Łączności. 2007
[3] H. Kaaraen, A. Ahtiainen, L. Laitinen, S. Naghian, V. Niemi: "UMTS Networks. Architecture, Mobility and Services" 2nd Edition, John Wiley & Sons Ltd. 2005
[4] A. Richardson: "WCDMA Design Handbook", Cambridge University Press 2005
[5] H. Holma, A. Toskala "WCDMA for UMTS - HSPA Evolution and LTE" 4th Edition,  John Wiley & Sons Ltd. 2007
[6] J. Bannister, P. Mather, S.Coope "Convergence Technologies for 3G Networks. IP, UMTS, EGPRS and ATM" John Wiley & Sons Ltd. 2004
[7] E. Dahlman, S. Parkvall, J. Sköld, P. Beming "3G Evolution - HSPA and LTE for Mobile Broadband" 2nd Edition, Elsevier Ltd. 2008
[8] J. Korhonen "Introduction to 3G Mobile Communications" 2nd Edition Artech House Inc. 2003
[9] H. Holma, A. Toskala "WCDMA for UMTS - HSPA Evolution and LTE" 5th Edition,  John Wiley & Sons Ltd. 2010
[10] "Basic Concepts of HSPA" - Ericsson White Paper - February 2007
[11] St. Maszczyk, J. Kołakowski, J. Cichocki "Techniki szybkiej transmisji danych w systemie UMTS" - Przegląd Telekomunikacyjny 10/2005
[12] HSPA+ Advanced Smart Networks: Multipoint Transmission  - Qualcomm Incorporated Feb 2011
[13] K. Johansson, J. Bergman, D. Gerstenberger, M. Blomgren, A. Wallén "Multi Carrier HSPA Evolution" - Ericsson
[14] Dual Cell HSDPA and its Future Evolution - Nomor Research January 2009
[15] HSPA+ Technology Introduction - White Paper - Rhode and Schwarz
[16] Continued HSPA Evolution of mobile broadband - Ericsson Review 1 2009
[17] Release 7 HSPA+ For Mobile Broadband Evolution - Qualcomm Incorporated Dec 2007
[18] LTE Advanced: Heterogeneous Networks - Qualcomm Incorporated Feb 2010
[19] Heterogeneous networks - increasing cellular capacity - Ericsson Review 1 2011
[20] 4G Mobile Broadband Evolution: Release 10, Release 11 and Beyond - HSPA, SAE/LTE and LTE-Advanced - 4G Americas
[21] Christopher Cox "An Introduction to LTE: LTE, LTE-Advanced, SAE and 4G Mobile Communications" John Wiley & Sons Ltd. 2012
[22] Voice Over LTE Volte - Anritsu Sep 2012
[23] E. Seurre, P. Savelli, P-J. Pietri "GPRS for Mobile Internet" 2003 ARTECH HOUSE

3GPP Specifications:
[23.401] General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio Access Network (E-UTRAN) access
[23.402] Architecture enhancements for non-3GPP accesses
[23.060] General Packet Radio Service (GPRS); Service description; Stage 2
[25.305] Stage 2 functional specification of User Equipment (UE) positioning in UTRAN
[36.300] Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2
[24.301] Non-Access-Stratum (NAS) protocol for Evolved Packet System (EPS); Stage 3

[21.905] Vocabulary for 3GPP Specifications