diff --git a/Doc/UserManual/Assemblies.tex b/Doc/UserManual/Assemblies.tex
index c2410d7b376189ea4e167ebe1d1387a33a19e765..c6b387659a993b3e26444a7a210734f087d50c42 100644
--- a/Doc/UserManual/Assemblies.tex
+++ b/Doc/UserManual/Assemblies.tex
@@ -562,7 +562,7 @@ correlation function is given by:
 Using standard relations for the Dirac comb,
 one obtains the interference function
 \begin{equation}
-  \SD(\q) = \frac{2\pi}{a}\sum_k \delta\left(q_x - \frac{2\pi k}{a}\right),
+   \SD(\q) = \frac{2\pi}{a}\sum_k \delta\left(q_x - \frac{2\pi k}{a}\right),
 \end{equation}
 which has the reciprocal lattice period $2\pi/a$.