Mixing Angle between 3P1 and 1P1 in HQET

Some claim that there are two independent mixing angles (theta = 35.3 degrees, -54.7 degrees) between P-3(1) and P-1(1) states of heavy-light mesons in the heavy quark symmetric limit, and others claim there is only one (theta = 35.3 degrees). We clarify the difference between these two and suggest which should be adopted. General arguments on the mixing angle between L-3(L) and L-1(L) of heavy-light mesons are given in HQET and a general relation is derived in the heavy quark symmetric limit as well as that including the first-order correction in 1/m(Q).