To add a video for Theodor Kirchner / Nachtbilder for piano, Op. 25: No. 8, Ruhig, singend, just enter the video‘s YouTube link:
example) https://www.youtube.com/watch?v=XXXXXXXXXXX
Search YouTube for Theodor Kirchner / Nachtbilder for piano, Op. 25: No. 8, Ruhig, singend