Several new high-spin states are observed in the prompt ␥-rays emitted from the neutron-rich, odd-Z 145,147 La fragments produced in the spontaneous fission of 252 Cf. Alternating parity bands are extended up to spins 41/2 and 43/2 in 145,147 La, respectively. A new band completes the evidence for two sets of parity doublets expected for octupole correlations. Eight B(E1)/B(E2) ratios ͑four new͒ between two bands in 145 La are all essentially constant and somewhat larger than similar ratios in 143,144 Ba, where stable octupole deformation and/or correlations are reported. The new ratios out of the 31/2 Ϫ levels in both nuclei show a sharp spike compared to other states, presumably from a strong reduction in E2 strengths in this backbending region. In 145 La, collective bands show competition and coexistence between symmetric and asymmetric shapes. Band crossings occur in both nuclei around បϷ0.26-0.30 MeV. Their backbends are associated with the alignment of two i 13/2 neutrons according to cranked shell model calculations. ͓S0556-2813͑99͒08402-2͔ PACS number͑s͒: 21.10. Re, 23.20.Lv, 27.60.ϩj, 25.85.Ca

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