\[ \boxed { {\frac {{\rm d}^{3}}{{\rm d}{x}^{3}}}y \left ( x \right ) + \left ( A{\it WeierstrassP} \left ( x,{\it g2},{\it g3} \right ) +a \right ) {\frac {\rm d}{{\rm d}x}}y \left ( x \right ) +B{\it WeierstrassPPrime} \left ( x,{\it g2},{\it g3} \right ) y \left ( x \right ) =0} \]
Mathematica: cpu = 0.012502 (sec), leaf count = 34 \[ \text {DSolve}\left [y'(x) (a+A \wp (x;\text {g2},\text {g3}))+B y(x) \wp '(x;\text {g2},\text {g3})+y^{(3)}(x)=0,y(x),x\right ] \]
Maple: cpu = 0.219 (sec), leaf count = 39 \[ \left \{ y \left ( x \right ) ={\it DESol} \left ( \left \{ {\frac { {\rm d}^{3}}{{\rm d}{x}^{3}}}{\it \_Y} \left ( x \right ) + \left ( A{ \it WeierstrassP} \left ( x,{\it g2},{\it g3} \right ) +a \right ) { \frac {\rm d}{{\rm d}x}}{\it \_Y} \left ( x \right ) +B{\it WeierstrassPPrime} \left ( x,{\it g2},{\it g3} \right ) {\it \_Y} \left ( x \right ) \right \} , \left \{ {\it \_Y} \left ( x \right ) \right \} \right ) \right \} \]