diff --git a/examples/sample.source.TAP3/Makefile b/examples/sample.source.TAP3/Makefile
index 0d6dbcd..3dfb47f 100644
--- a/examples/sample.source.TAP3/Makefile
+++ b/examples/sample.source.TAP3/Makefile
@@ -679,7 +679,7 @@
 # This file may be used as an input for make(3)
 # Remove the lines below to convert it into a pure .am file
 TARGET = tap3dump
-CFLAGS += -I. -DHAVE_CONFIG_H -DPDU=DataInterChange
+CFLAGS += -I.  -DHAVE_CONFIG_H -DPDU=DataInterChange
 OBJS=${ASN_MODULE_SOURCES:.c=.o} ${ASN_CONVERTER_SOURCES:.c=.o}
 
 all: DataInterChange.c $(TARGET)