Slight beautification

grid_models.md

@@ -107,7 +107,8 @@ Parameter codes are not necessarily self explanatory. E.g. in the PSILARTEMP mod
 
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-    The warning system model &laquo;Carrot rust fly temperature&raquo; is based on a Finnish temperature-based model (Markkula <em>et al</em>, 1998; Tiilikkala &amp; Ojanen, 1999; 
+    The warning system model &laquo;Carrot rust fly temperature&raquo; is based on a Finnish 
+    temperature-based model (Markkula <em>et al</em>, 1998; Tiilikkala &amp; Ojanen, 1999; 
     Markkula <em>et al</em>, 2000). The model determines the start of the flight period for 
     the 1st and 2nd generation of carrot rust fly based on accumuleted degree-days (day-degrees) 
     over a base temperature of 5,0 &deg;C. VIPS uses the model for the 1st generation only.