[Natural Scale, 1:10054; 1910] https://www.libraryceo.com/hkugeog/opac/?page=opacInfo&id=0094989

[Natural Scale, 1: 1000000; 1910] https://www.libraryceo.com/hkugeog/opac/?page=opacInfo&id=0095769

[Natural Scale, 1:25,500; 1923] https://www.libraryceo.com/hkugeog/opac/?page=opacInfo&id=0094988

[Natural Scale, 1:25000; 1923] https://www.libraryceo.com/hkugeog/opac/index.php?page=opacInfo&id=0095921

[1925] https://www.libraryceo.com/hkugeog/opac/?page=opacInfo&id=0094992

[Natural scale, 1:50,0000; 1926] https://www.libraryceo.com/hkugeog/admin/lib_cataloguing.php?action=info&rid=0095557

[Natural scale, 1:500,000; 1927] https://www.libraryceo.com/hkugeog/opac/?page=opacInfo&id=0095794

[Natural Scale, 1: 100000; 1927] https://www.libraryceo.com/hkugeog/opac/?page=opacInfo&id=0095896

[Natural Scale, 1:2000000; 1932] https://www.libraryceo.com/hkugeog/opac/?page=opacInfo&id=0095778

[Natural Scale, 1: 100,000; n.d] https://www.libraryceo.com/hkugeog/opac/?page=opacInfo&id=0095845

[Natural Scale, 1:20000; 1950] https://www.libraryceo.com/hkugeog/opac/?page=opacInfo&id=0095771