Sorry about that. The article obviously doesn't explain. Here's my thoughts on it.
I don't think they did any exhaustive research. They didn't have to.
You would be able to look at the crater and see sizable pieces of a military air-dropped bomb. Normal bombs don't disintegrate. If they send it to a lab they can tell what explosive was used in it, which will roughly tell you when it was manufactured. (Assuming they don't find a serial number.)
That by itself is hardly conclusive, but that completely changes when you find identical unexploded bombs buried in the same area.
It would be rather odd if somebody came along later and put the same kind of bomb used in WWII in the ground. When the bomb got there isn't that important.
I don't think they did any exhaustive research. They didn't have to.
You would be able to look at the crater and see sizable pieces of a military air-dropped bomb. Normal bombs don't disintegrate. If they send it to a lab they can tell what explosive was used in it, which will roughly tell you when it was manufactured. (Assuming they don't find a serial number.)
That by itself is hardly conclusive, but that completely changes when you find identical unexploded bombs buried in the same area.
It would be rather odd if somebody came along later and put the same kind of bomb used in WWII in the ground. When the bomb got there isn't that important.