I would love to have a US source for paper cake liners shown in the Honey Cake with Dates and Apples.
Nigella's Honey Cake With Dates And Apples is baked in a 20cm/8-inch springform pan. In the recipe intoroduction Nigella mentions that she uses round paper cake liners for the tins. These make removing the cake very easy and are also useful if the cake is being given as a gift, as the liner provides some extra wrapping.
It is probably easiest to find the paper liners on-line and brands to look for include Tala, Lakeland, Baker's Pride and Kitchen Craft. The liners may also be described as "siliconised" or "non-stick". If the liners prove elusive, it is possible to buy ready cut circles for the bottom of the pans plus a smaller roll of baking parchment (parchment paper), described as a "side liner roll", that can be used for the sides of the pan. However, the cake will still release easily from the springform pan if the pan is lined on the base with a circle of baking parchment and the sides are greased with some vegetable oil.