$v_2$ as a function of $\pt$ in the 30-50% centrality class, for $\rm D^0$, $\rm D^+$ and $\rm D^{*+}$ mesons (rows) with the event plane, scalar product and two-particle cumulant methods (columns). For the first method, the event plane was estimated with TPC tracks in $0< \eta< 0.8$; for the other methods, TPC tracks in $-0.8< \eta< 0.8$ were used as RFP. The symbols are positioned at the average $\pt$ measured within each interval.