diff --git a/src/core/sale.cpp b/src/core/sale.cpp
new file mode 100644
index 0000000..8407232
--- /dev/null
+++ b/src/core/sale.cpp
@@ -0,0 +1,10 @@
+#include "sale.h"
+
+#include <numeric>
+
+int Sale::sumInCents()
+{
+    int test = std::accumulate(articles_.begin(), articles_.end(), 0,
+                               [](int a, Article* b) { return a + b->getPrice(); });
+    return test;
+}
\ No newline at end of file
diff --git a/src/core/sale.h b/src/core/sale.h
index 06f350d..e4d016e 100644
--- a/src/core/sale.h
+++ b/src/core/sale.h
@@ -1,8 +1,21 @@
 #ifndef SALE_H
 #define SALE_H
 
-class Sale : public Entity {
+#include "article.h"
 
+#include <vector>
+
+#include <boost/date_time.hpp>
+
+class Article;
+
+class Sale : public Entity
+{
+  public:
+    int sumInCents();
+  private:
+    boost::posix_time::ptime systemTime_{boost::posix_time::second_clock::local_time()};
+    std::vector<Article*> articles_{};
 };
 
 #endif
\ No newline at end of file