diff --git a/src/apatite/linear_algebra/matrix.cr b/src/apatite/linear_algebra/matrix.cr
index aecda84..510ee79 100644
--- a/src/apatite/linear_algebra/matrix.cr
+++ b/src/apatite/linear_algebra/matrix.cr
@@ -1,4 +1,5 @@
 require "json"
+require "./vector"
 require "./matrix/eigenvalue_decomposition"
 require "./matrix/lup_decomposition"
 
diff --git a/src/apatite/linear_algebra/vector.cr b/src/apatite/linear_algebra/vector.cr
index 07f9a1a..74c279c 100644
--- a/src/apatite/linear_algebra/vector.cr
+++ b/src/apatite/linear_algebra/vector.cr
@@ -1,4 +1,5 @@
 require "json"
+require "./matrix"
 
 module Apatite::LinearAlgebra
   # Represents a mathematical vector, and also constitutes a row or column