Sneutrino production at e + e - linear colliders: addendum to slepton production A. Freitas, A. von Manteuffel and P. M. Zerwas Eur. Phys. J. C, 40 3 (2005) 435-445 Published online: 15 April 2005 DOI: 10.1140/epjc/s2005-02148-6