Anne,
I certainly second the recommendation of Murphy’s 1996 article made to you by Robert Kerr in his 23 January message.
Below I add some further references that you may want to consider, if you haven’t already incorporated them. I am not clear if by "frontier" you mean a linear international boundary or an areal frontier zone, so I will specify which is involved in each case.
A. Regarding the development of the Westphalian sovereign state concept in general, the following (in addition to Murphy 1996) may also be useful:
Cobban, Alfred (1994) "The Rise of the Nation-State System," in John Hutchinson and Anthony D. Smith, Nationalism (Oxford, New York: Oxford University Press), pp. 245-250
Hobsbawm, Eric (1990) Nations and nationalism since 1780 (Cambridge, New York, yet al.: Cambridge University Press), Chap. 1, pp. 14-45
Shaw, Malcolm (1986) Title to Territory in Africa: International Legal Issues (Oxford: Clarendon Press), "Introduction: Territory in International Law," pp. 1-26
Taylor, Peter J. (1994) "The state as container: territoriality in the modern world system," Progress in Human Geography, 18 (2), pp.151-162; esp. pp. 152-157
Tilly, Charles (1975) The Formation of National States in Western Europe (Princeton: Princeton University Press)
B. If you are interested in frontiers as zones and their conversion into linear international boundaries, you might want to look at:
Prescott, J.R.V. (1987) Political Frontiers and Boundaries (London, Boston, Sydney, Wellington: Allen & Unwin), Chap. 2, "Frontiers," pp. 36-57. Also available in _______ (1978) Boundaries and Frontiers (London: Croom Helm), pp.32-52
Shaw, Malcolm (1986) Title to Territory in Africa: International Legal Issues (Oxford: Clarendon Press), pp. 28-30
C. With regard to pre-Westphalian Asian and African concepts of borders or frontiers or the introduction of the Westphalian sovereign state and/or linear state boundary concepts to non-European areas, the following should be of interest:
Barnett, Michael (1996), "Sovereignty, nationalism, and regional order in the Arab states system," in Thomas J. Biersteker and Cynthia Weber (eds.) State Sovereignty as Social Construct (Cambridge: Cambridge University Press), pp. 148-189
Black, Jeremy (1997) Maps and Politics (Chicago: University of Chicago Press), pp. 31-32 ("Euro-Asian frontiers")
Brownlie, Ian (1979) African Boundaries: A Legal and Diplomatic Encyclopedia (Berkeley and Los Angeles, University of California Press), pp. 9-12
Hill, R.D. (1991) "Fishing in Troubled Waters: Some Thoughts on Territorial Claims in the South China Sea," in Fishing in Troubled Waters: Proceedings of an Academic Conference on Territorial Claims in the South China Sea (Hong Kong: University of Hong Kong, Centre of Asian Studies), pp. 2-3
Husmann, Lisa (1994) " ‘National Unity’ and National Identities in the People’s Republic of China," in David Hooson (ed.) Geography and National Identity (Oxford UK and Cambridge US: Blackwell), pp. 141-157 (esp. pp. 145-147)
Joffé, George (1994) "Territory, State and Nation in the Middle East and North Africa," in Clive H. Schofield and Richard N. Schofield (eds.) The Middle East and North Africa, World Boundaries Volume 2 (London and New York: Routledge), pp.1-20
Li, Victor H. (1979) "Sovereignty at Sea: China and the Law of the Sea Conference," Stanford Journal of International Studies, v.15, pp. 225-245 (esp. pp. 226-232)
Prescott, J.R.V. (1987) Political Frontiers and Boundaries (London, Boston, Sydney, Wellington: Allen & Unwin), Chap. 2, "Frontiers"; Chap. 3, "Evolution of Boundaries," pp. 36-92. Also available in _______ (1978) Boundaries and Frontiers (London: Croom Helm), pp.33-88
Prescott, J.R.V. (1975) Map of Mainland Asia by Treaty (Melbourne). (This work provides a detailed, documented history of the making of each boundary, while the introduction outlines the geopolitical circumstances in which boundaries evolved in each of three historical phases of boundary fixing in Asia.)
Samuels, Marwyn (1982) Contest for the South China Sea (New York, London: Methuen), p. 51
Shaw, Malcolm (1986) Title to Territory in Africa: International Legal Issues (Oxford: Clarendon Press), Chap. I, "The Colonization of Africa," pp. 27-58
Soja, Edward (1971) The Political Organization of Space, Commission on College Geography, Research Paper No. 8 (Washington, DC: Association of American Geographers), pp. 9-11
Tilly, Charles, "Europe and the International State System," in John Hutchinson and Anthony D. Smith, Nationalism (Oxford, New York: Oxford University Press), pp. 251-254
D. I am working on a paper on the consequences of the present international boundaries in Central Asia imposed earlier by the Soviets, for which the following are quite informative:
"Conflict in Post-Soviet Transitions: Central Asia and the Caucasus," Conference sponsored by The Center for Political and Strategic Studies and the Kyrgyz National State University, Bishkek, Kyrgyzstan, 22August 1997, "Synopsis of Proceedings," CPSS website [www.cpss.org/confrep.htm]
Dannreuther, Roland (1994) Creating New States in Central Asia: The strategic implications of the collapse of Soviet power in Central Asia. Adelphi Paper No. 288 (London: The International Institute for Strategic Studies), pp. 7-19
Hooson, David (1994) "Ex-Soviet Identities and the Return of Geography," in David Hooson (ed.) Geography and National Identity (Oxford UK and Cambridge US: Blackwell), pp. 134-140
Sanford, William E. (1997) "Central Asia and the Caucasus: Historical Legacies and Future Challenges," Perspectives on Central Asia, Center for Political and Strategic Studies (CPSS) website [www.cpss.org/casianw/canews.htm], April, p. 3
Shaw, Dennis J.B. (1995) "Ethnic relations and federalism in the Soviet era", in Dennis J.B. Shaw (ed.) The Post Soviet Republics: A Systematic Geography (Harlow UK: Longman Group Ltd.), pp. 23-33 (esp. pp. 26-28)
Tishkov, Valery (1997) Ethnicity, Nationalism and Conflict in and after the Soviet Union: The Mind Aflame (London, Thousand Oaks CA, New Delhi: Sage Publications), pp. 27-35
I hope these are helpful. I would certainly welcome any additions which int-boundaries colleagues would care to make to this short list.
Brad Thomas
Department of Geography
The George Washington University
Washington, DC