General :: External DVD-RW (ASUS) - Which /dev/ File Associated With External Dvdrom

I plugged in my external dvd-r (asus) via usb. It showed me some message on shell, that it has detected the cdrom(although its dvd rom as well but nevermind) and its of ASUS. But how do i know which dev it was associated with in /dev/? Since i had to test something, i plugged it out, and save the output of ls /dev/ > ~/result.txt

after plugging the dvd-rom, i compared the results and was able to find that it was associated with simple cdrom i.e. /dev/cdrom. I wanted to know that is there any command that will tell me which /dev/ file was associated with external dvdrom? i tried to see in the following result

1) df -h ( no results, just the already mounted partitions)
2) fdisk -l ( same as above)
3) dmesg | tail (shown almost the same result as was shown on shell at the time of plugging the dvd)