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2. See e.g., Cheng, B., ‘United Nations Resolutions on Outer Space: “Instant” International Customary Law?’, 5 Indian JIL (1965) pp. 23–48, at p. 36Google Scholar, criticized by, e.g., Verdross, A. and Simma, B., Universelles Völkerrecht, 3rd edn. (1984) pp. 358 and 361–362Google Scholar. The necessity of practice has also been strongly emphasized by the World Court, among others in the Nicaragua Judgment (Merits), ICJ Rep. (1986) p. 98, para. 184.

3. E.g., Müller, J.P., Vertrauenschutz im Völkerrecht (1971) pp. 258–260Google Scholar, does not base international custom on any acceptance but on the expectation that the practice will continue.

4. Para. 1(b): ‘International custom, as evidence of general practice accepted as law.’ See Wolfke, K., Custom in Present International Law (1964) pp. 20–28Google Scholar. In the last decade see e.g., the Nicaragua Judgment (Merits), ICJ Rep. (1986) pp. 97–98, para. 27.

5. See Haggenmacher, P., ‘La doctrine des deux éléments du droit coutumier dans la pratique de la Cour internationale’, 90 RGDIP (1986) pp. 5–125, at p. 114.Google Scholar

6. See e.g., the statements in the Norwegian Fisheries case (ICJ Rep. (1951) p. 138) and in the Nicaragua case (Merits) (ibid., (1986) pp. 98–99).

7. See e.g., Akehurst, M., ‘Custom as a Source of International Law’, 47 BYIL (1974-1975) pp. 1–8Google Scholar; Villiger, M.E., Customary International Law and Treaties (1985) pp. 5–7.Google Scholar

8. See 40 AJIL (1946) Supp. 45.

9. E.g., Danilenko, G.M., ‘The Theory of Customary International Law’, 31 GYIL (1988) p. 21.Google Scholar

10. E.g., Danilenko regards customary law formation as ‘a deliberate law-creating process’, ibid., p. 14.

11. See Puchta, G., Das Gewohnheitsrecht, vol. III (1828) pp. 24–119, at pp. 33–39Google Scholar; Guggenheim, P., ‘Contribution l'histoire des sources du droit des gens’, 94 RCADI (1958-II) p. 53Google Scholar; Sørensen, M., Les sources du droit international (1946) pp. 105–111.Google Scholar

12. See e.g., The Canadian Arctic Waters Pollution Bill of 1970, 9 ILM (1970) pp. 543–554Google Scholar; see also Henkin, L., ‘Arctic Anti-Pollution: Does Canada Make – or Break – International Law?’, 65 AJIL (1971) pp. 131–136.CrossRefGoogle Scholar

13. Wolfke, op. cit. n. 4, pp. 20–58. See also infra.

14. ICJ Rep. (1969) p. 43, para. 74.

15. Ibid., p. 44, para. 77.

16. Ibid., p. 44, para. 78. This definition reads as follows: ‘The rules of law binding upon States … emanate from their own will as expressed in conventions or by usages generally accepted as expressing principles of law …’, PCIJ, Ser. A 10, p. 18. P. Manin did not exclude that the apparent inconsistency in the 1969 Judgment was caused by the Court giving satisfaction to certain of its members favourable to a renovation of the theory of custom: ‘Le juge international et la règle générale’, 80 RGDIP (1976) no. 1, p. 35.Google Scholar

17. ICJ Rep. (1986) pp. 97–98, para. 184.

18. Idem.

19. Ibid., para. 185; see also ibid., pp. 99–100, para. 188; p. 101, para. 191;andp. 102, para. 193.

20. E.g., Meijers' interesting detailed three-stage model of custom generation is also far from rigid, for the stages ‘can coincide, wholly or in part’. Meijers, H., ‘How is International Law Made? – The Stages of Growth of International Law and the Use of its Customary Rules’, 9 NYIL (1978) pp. 3–26, at p. 6.CrossRefGoogle Scholar

21. A different view is represented by D'Amato, who regards ‘articulation’ of customary rules as the indispensable qualitative element of international custom: D'Amato, A.A., The Concept of Custom in International Law (1971) pp. 74–87.Google Scholar

22. Ibid., pp. 97–98.

23. See e.g., ICJ Rep. (1986) pp. 108–109, para. 207.

24. Ibid., p. 98, para. 186; see also Czapliński, W. and Danilenko, G., ‘Conflicts of Norms in International Law’, 21 NYIL (1990) pp. 31–32.CrossRefGoogle Scholar

25. Akehurst, loc. cit. n. 7, p. 8.

26. See e.g., Charney, J.I., ‘The Persistent Objector Rule and the Development of Customary International Law’, 58 BYIL (1987) pp. 2–24.Google Scholar

27. Ibid., pp. 21–24. Seealso, e.g., Colson, D.A., ‘How Persistent Must the Persistent Objector Be?’, 61 Washington LR (1986) pp. 957–971.Google Scholar

28. E.g., D'Amato, op. cit. n. 21, pp. 70, 98–102.

29. See e.g., Cassan, H., ‘Le consensus dans la pratique des Nations Unies’, 20 AFDI (1974) pp. 146–185CrossRefGoogle Scholar; Zemanek, K., ‘Majority Rule and Consensus Technique in Law-Making Diplomacy’, in MacDonald, R.S.J., Johnston, D.M. and Morris, G.L., eds., Structure and Process of International Law, Essays in Legal Philosophy, Doctrine and Theory (1983) pp. 857–887.Google Scholar

30. This requirement was, for example, evidently fulfilled in the Fisheries case of 1974, ICJ Rep. (1974) pp. 23 and 191–192.

31. See e.g., Baxter, R.R., ‘Treaties and Custom’, 129 RCADI (1970-I) pp. 25–106Google Scholar; Karl, W., Vertrag und spätere Praxis im Völkerrecht (1983)Google Scholar; Villiger, op. cit. n. 7.

32. E.g., D'Amato without reservation maintains that ‘generalizable provisions in bilateral and multilateral treaties generate customary rules binding all States’. Op. cit. n. 21, p. 104.

33. See e.g., ICJ Rep. (1969) pp. 41–44.

34. See e.g., Lammers, J.G., Pollution of the International Watercourses. A Search for Substantive Rules and Principles (1984) pp. 155–160.Google Scholar

35. See e.g., JrGamble, J.K.. and Frankowska, M., ‘The 1982 Convention and Customary Law of the Sea: A Framework, and a Warning’, 21 San Diego LR (1984) pp. 491–511Google Scholar; Bernhardt, R., ‘Custom and Treaty in the Law of the Sea’, 205 RCADI (1987-V) pp. 247–330.Google Scholar

36. See recently, Czapliński and Danilenko, loc. cit. n. 24, pp. 35–41.

37. Ibid., pp. 37–38.

38. See the opinion on Namibia, ICJ Rep. (1971) p. 22.

39. E.g., Tunkin, G.I., Voprosy Teorii Meshdunarodnogo Prava (1962) pp. 112–113.Google Scholar

40. ICJ Rep. (1986) pp. 94–95, paras. 176–178. Per contra, Czapliński, W., ‘Sources of International Law in the Nicaragua Case’, 38 ICLQ (1989) pp. 151–166, at pp. 164–166.CrossRefGoogle Scholar

41. The comparison was used by Baxter, R. R. in ‘Multilateral Treaties as Evidence of Customary International Law’, 41 BYIL (1965-1966) at p. 299.Google Scholar

42. Among the latter, e.g., MacGibbon, I., ‘Means for the Identification of International Law. The General Assembly Resolutions' Custom, Practice and Mistaken Identity’, in Cheng, B., ed., International Law: Teaching and Practice (1982) pp. 10–23Google Scholar; Schwebel, S.M., ‘United Nations Resolutions. Recent Arbitral Awards and Customary International Law’, in Realism in International Law, Essays on International Law in Honour of Willem Riphagen (1986) pp. 205–210.Google Scholar

43. Here again the example of the customary amendment of the UN Charter by the practice of the Security Council should be mentioned. See supra, n. 38.

44. For a similar opinion see e.g., Skubiszewski, K., Resolutions of the General Assembly of the United Nations and Draft Resolutions. Definite Report for the Institute of International Law, Session d'Helsinki, vol. 61(I) (1985) p. 330 (Conclusion 27).Google Scholar

45. See ibid., p. 321 (Conclusion 13).

46. See e.g., Vitanyi, B., ‘Les positions doctrinales concernant le sens de la notion de “Principes généraux de droit reconnus par les nations civilisées”’, 86 RGDIP (1982) pp. 48–116.Google Scholar

47. See the Free Passage case, ICJ Rep. (1960) p. 39.

48. E.g., Schwarzenberger, I.C.G., International Law, vol. I, 3rd edn. (1957) p. 15.Google Scholar

49. E.g., Fitzmaurice, G., justifying the automatic binding forceof customary international law, compared the legal status of newly emerged States to that of a new-born child: ‘The General Principles of International Law Considered from the Standpoint of the Rule of Law’, 92 RCADI (1957-II) p. 46.Google Scholar

50. See e.g., Fitzmaurice, G., ‘The Law and Procedure of the International Court of Justice 1951–1954: General Principles and Sources of Law’, 29 BYIL (1953) pp. 68–69Google Scholar; ICJ Rep. (1982) p. 74.

51. ICJ Rep. (1948) p. 120.

52. E.g., Morelli, G., ‘Cour général de droit international public’, 89 RCADI(1956-I) p. 453Google Scholar; Verdross and Simma, op. cit. n. 2, pp. 362–364.

53. See recently, e.g., Czapliński and Danilenko, op. cit. n. 24, pp. 8–12.

54. E.g., in the Nicaragua Judgment (Merits) the Court only referred to the view of the International Law Commission in its Commentary on the draft articles on the Law of Treaties. ICJ Rep. (1986) pp. 100–101, para. 190.

55. See Wolfke, K., ‘Jus Cogens in International Law. Regulation and Prospects’, 6 Polish YIL (1974) pp. 145–162Google Scholar; van Hoof, G.J.K., Rethinking the Sources ofInternational Law (1983) pp. 151–167.Google Scholar

56. See Ways and Means of Making the Evidence of Customary International Law More Readily Available (Memorandum submitted by the Secretary-General) (1949).

57. E.g., D'Amato, A.A., ‘Trashing Customary International Law’, 81 AJIL (1987) pp. 101–105CrossRefGoogle Scholar; JrKirgis, F.L.., ‘Custom on a Sliding Scale’, 81 AJIL (1987) pp. 145–151.CrossRefGoogle Scholar

58. E.g., van Hoof, op. cit. n. 55, pp. 113–116.

59. The development and codification of the law of the sea convincingly illustrates this.