Authors: B E Clarke; S E Newton; A R Carroll; M J Francis; G Appleyard; A D Syred; P E Highfield; D J Rowlands; F Brown Journal: Nature Date: 1987 Nov 26-Dec 2 Impact factor: 49.962
Authors: F Delpeyroux; N Chenciner; A Lim; Y Malpièce; B Blondel; R Crainic; S van der Werf; R E Streeck Journal: Science Date: 1986-07-25 Impact factor: 47.728