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Now I have always known that you could not make an infinite lava source. However in your book it says you can.

"...place 4 Nether brick in a cross shape, then use a lava bucket in the centre. This will create an infinite lava source." - Minecraft: Combat Handbook, Stephanie Milton, Mojang, Ergmont (2014), United Kingdom of Great Britain and Northern Ireland.

After following these instructions, I discovered that to no surprise the books were (once again) wrong.
As your official material states that you can make something that is not possible (ie. an infinite lava source) I am going to call this a bug. And I hope that it is fixed soon.

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