Brockhaus-1911: Portland · Portland [2] · Portland [3] · Duncansby Head · Beachy Head · Lizard Head · Dungsby Head
Herder-1854: Portland · Portland Vase · Head
Meyers-1905: Portland [2] · Portland [1] · Portland [3] · South Portland · Portland [4] · Duncansby Head · Dunmore Head · Benmore Head · Spurn Head · Beachy Head · Flamborough Head · Fair Head · Head · Dunnet Head · Orme's Head, Great
Pierer-1857: Portland-Islands · Portland [2] · Portland [1] · Portland-Vase · Hoath-Head · Hog's Head · Holburn-Head · Helwick-Head · Hagß-Head · Head · Head-Harbour · Bolt-Head · Spurn Head · Red-Head · Mumbles-Head · Innishowen-Head · Kinnaird's Head · Maiden-Head · Gowens Head, St. · Bray-Head · Brandon-Head · Dondra Head · Davids-Head · Blore Head · Ardmore Head · Abbs-Head · Beachy Head · Bald-Head · Gally-Head · Fitful-Head · Govens Head, St. · Gay-Head · Faront-Head · Dungisby-Head · Dowlas Head · Dunorling-Head · Dunmore-Head