diff --git a/Partial-Overlaps-of-Many-Body-Wavefunctions.md b/Partial-Overlaps-of-Many-Body-Wavefunctions.md
index c4cdecc..93f8b72 100644
--- a/Partial-Overlaps-of-Many-Body-Wavefunctions.md
+++ b/Partial-Overlaps-of-Many-Body-Wavefunctions.md
@@ -13,7 +13,7 @@ orthogonal than others.
 
 Formally, one can start from
 \[
-PO_{ab} (s) = \int_0^{L-s} dx \psi^\dagger_a \psi_b
+PO\_{ab} (s) = \int\_0^{L-s} dx \psi^\dagger\_a \psi\_b
 \]
 with $s$ between $0$ and $L$.