“Can a hamburger marry a hot dog?”/“Only if they have a very frank relationship.”

A hamburger and hot dog riddle is:
 
Q: Can a hamburger marry a hot dog?
A: Only if they have a very frank relationship.
 
The joke was included in the book 101 Hamburger Jokes (1978) by Phil Hirsch.
 
             
Google Books
101 Hamburger Jokes:
Meaty jokes to be devoured with relish
By Phil Hirsch
Illustrated by Don Orehek
New York, NY: Scholastic Book Services
1978
Pg. 21:
Can a hamburger marry a hot dog?
Only if they have a very frank relationship!
 
6 September 1981, The Star-News (Chula Vista, CA), “Humor: One alternative to tension” by Sandy Pasqua, pg. B-5, col. 2:
“Can a hamburger marry a hot dog? Only if they have a very frank relationship.”
(From the book 101 Hamburger Jokes.—ed.)
 
12 November 1989, Washington (DC) Post, “Mighty Funny’s Mini Jokes,” The Mini Page, pg. 3, col. 2:
Q: Can a hamburger marry a hot dog?
Mighty Funny: Only if they have a very frank relationship.
(Sent in by Margalie Deshommes)
 
Twitter
Dyan_Meira7‏
@Dyan_Meira7
Can a hamburger marry a hot dog? Only if they have a very frank relationship!
3:32 PM - 3 Oct 2009
   
Google Groups: Rotary Cebu West
FW: FUNNY Q & As ABOUT FAST FOOD
Dapat, Sabino
4/29/14
(...)
Q: When can a hamburger marry a hot dog?
A: After they have a very frank relationship!
   
Google Books
Fast Food Jokes For Kids
By Jack Jokes
PeteyRF Creative
2016
Pg. ?:
When can a hamburger marry a hot dog?
After they have a very frank relationship!
 
Twitter
Lucky Score‏
@LuckyScoreNet
Can a hamburger marry a
hot dog?
Only if
they have a very frank relationship!
#Joke from #BurgerJokes in #Jokes, #Humor and #Satire
3:36 PM - 16 Oct 2017