Biharmonic curves on \textit{LP}-Sasakian manifolds
  In this paper we give necessary and sufficient conditions for spacelike and timelike curves in a conformally flat, quasi conformally flat and conformally symmetric 4-dimensional \textit{LP}-Sasakian manifold to be proper biharmonic. Also, we investigate proper biharmonic curves in the Lorentzian sphere $S^{4}_{1}$. 
Sad{\i}k Kele\c{s}, Selcen Y\"uksel Perkta\c{s}, Erol K{\i}l{\i}\c{c}