Update, 26 Oct 2018: And the winner is ...

... the rickshaw cover.

Thank you to everyone who voted. Across Facebook, Gwulo and Twitter there were a total of 200 votes, with 78 for the children cover and 122 for the rickshaw cover.

Whichever photo you preferred, you can take a closer look when you see the book. Both photos are shown there, enlarged as double-page spreads.

The layout of the new book's cover will be very similar to the first book, but this time using a blue colour instead of red.

If you go walking in the hills behind Kowloon, you'll likely have seen raised, concrete slabs like these:

Most of Warren Swire's photographs show buildings and scenery, so this close-up photo of a group of people is a rarity.