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The excited states of the odd-odd 154Ho nucleus have been studied by using in-beam y-ray spectroscopy with the 141Pr (16O, 3n) l54Ho reaction at Elab = 75 MeV The beam was provided by the 12UD Pelletron accelerator at the University of Tsukuba. In this work, the complicated decay pattern of low energy transitions just above the T1/2 = 3.10 min isomer have been established. In addition, a number of new states and y-ray transitions, especially those associated with energetically favored band termination, have been observed for the first time in 154Ho. A negative collective band and its signature partner built on the 11- level are interpreted as being based on the πh11/2 ⊗ vi13/2 configuration. A positive band built on the 10+ level is based on the πh11/2 ⊗ vi13/2 configuration while another positive band built on the 9+ level is being associated with the πh11/2 ⊗ Vh9/2 configuration. An energetically favored level Jπ = 19- can be interpreted as being attributed to the πh 11/2 ⊗ vi13/2 configuration coupled to the 8+ state in neighboring core 152Dy, namely, a four-quasiparticle alignment based on the [πh 11/2vi 13/2]11- ⊗[v(h9/2f7/2)]8- configuration. Another energetically favored state at Jπ = 27- is assigned the six-quasiparticle [π(h11/2)³]27/2-⊗[v(f7/2h9/2l13/2)]27/2- configuration. [ABSTRACT FROM AUTHOR]