diff --git a/src/plastic_dislotwin.f90 b/src/plastic_dislotwin.f90
index c7aaf5400..68c45fd8e 100644
--- a/src/plastic_dislotwin.f90
+++ b/src/plastic_dislotwin.f90
@@ -265,6 +265,10 @@ subroutine plastic_dislotwin_init(fileUnit)
  real(pReal), dimension(:), allocatable :: tempPerSlip, tempPerTwin, tempPerTrans
   
  write(6,'(/,a)')   ' <<<+-  constitutive_'//PLASTICITY_DISLOTWIN_label//' init  -+>>>'
+ write(6,'(/,a)')   ' A. Ma and F. Roters, Acta Materialia, 52(12):3603–3612, 2004'
+ write(6,'(/,a)')   ' https://doi.org/10.1016/j.actamat.2004.04.012'
+ write(6,'(/,a)')   ' F.Roters et. al , Computational Materials Science, 39:91–95, 2007'
+ write(6,'(/,a)')   ' https://doi.org/10.1016/j.commatsci.2006.04.014'
  write(6,'(a15,a)') ' Current time: ',IO_timeStamp()
 #include "compilation_info.f90"