Detecting your Love - Sherlock Holmes and Other Detectives

I'm going to stop looking -- I know I'll like your cooking -- Oh boy! You and me.

4 3/4" x 11"  opened
circa 1930s
   Folded
  marked: Made in U.S.A.
no other publisher's marks

I'm on your Trail, Dear Valentine ~  I do suspect That you detect I want you to be mine, So here's a clue To prove to you I'd like to be Your Valentine!

4 1/4" x 5 1/4" (5 1/4" x 8 1/2" opened)
circa 1930s, 1940s
  French Fold
 made in USA
by Golden Bell
 marked: 0 7322B

Valentine no SHERLOCK HOLMES need I be - to see you really care for me!

7 1/4" x 4 1/4"
circa 1950s
Mechanical Flat
marked: made in U.S.A.
no other publisher's marks 

Valentine You're the one I'm LOOKING FOR!

Fold-Out
circa 1950s
no publisher's marks

I like you a lot!  This is no MYSTERY to me.

figure with magnifying glass
circa 1950s
Flat
marked: made in USA
no other publisher's marks