No Serial Number?

Update: I found the serial number on this bike, thanks to this linked website. However, the paint is applied so heavily that I can't read the number. Instead, I recorded the Minneapolis bike registration sticker numbers. 1981-83: 2027124, 1978-80: 8051375

When this bike is out of the bomb shelter and on the road, it can only mean one thing; the Lake Pepin 3-Speed Tour is near.

In an effort to continue recording serial numbers of my bikes, I tried to find one on this machine. But I can't find it. I can't find one on my other 3-speed either.

The presence of this little house along my ride to work can only mean one thing; it's spring and I've ridden along the sidewalk that borders the golf course.