1. International Institute of Tropical Agriculture (IITA), IITA (UK) Ltd; Carolyn House, 26 Dingwall Rd. Croydon CR9 3EE United Kingdom
2. CRI-CSIR; Box 3785 Kumasi Ghana
3. INRAB; Cotonou Benin Republic
4. IAR; Amadu Bello Univ.; Samaru Nigeria
5. SARI-CSIR; Box 52 Tamale Ghana