diff --git a/megaradrp/recipes/auxiliary/focusspec.py b/megaradrp/recipes/auxiliary/focusspec.py
index e0563053..130a6135 100644
--- a/megaradrp/recipes/auxiliary/focusspec.py
+++ b/megaradrp/recipes/auxiliary/focusspec.py
@@ -33,6 +33,7 @@
 from numina.exceptions import RecipeError
 import numina.array.utils
 import numina.array.fwhm as fmod
+import numina.core.validator
 from numina.array.stats import robust_std as sigmaG
 from numina.array.peaks.peakdet import find_peaks_indexes, refine_peaks