a) The observed abundances can be explained by capture of fast neutrons,
b) if the time integral of the neutron density has a certain value.
c) However, as this integral diverges at t=0, it is necessary to assume
1) the temperature was so high that the nuclei disintegrated, or
2) the density of the Universe never exceeded a certain value.
d) "The building-up process was apparently completed when the temperature
of the neutron gas was still rather high, since otherwise the observed
abundances would have been strongly affected by the resonances in the
region of the slow neutrons". The cold cloud of neutrons is abandoned.