diff --git a/docs/ics_format.txt b/docs/ics_format.txt
index 4becc78..f1adc42 100644
--- a/docs/ics_format.txt
+++ b/docs/ics_format.txt
@@ -2,6 +2,10 @@ RFC5545
 -------
 https://www.rfc-editor.org/rfc/rfc5545
 
+The iCalendar object is organized into individual lines of text,
+called content lines. Content lines are delimited by a line break,
+which is a CRLF sequence (CR character followed by LF character).
+
 
 ICS files from Microsoft Outlook differ from those that were created by Gnome Evolution.
 (semicolons are used instead of colons at some position)