The balance between $N_A$ and $N_B$ is destroyed at e.g. zigzag edges, which may provide a low-temperature background magnetism observed in a graphene sample [@skmt18].

Recent investigation of a graphene sheet by controllable doping it with fluorine adatoms and creation of vacancies by irradiation [@snrn10; @nstl12; @ntsl13] has indicated that both defects induce a magnetic moments with spin $1/2$. Nevertheless, they do not result in a magnetic ordering, rather an induced paramagnetism down to liquid helium temperatures was observed in the doped samples. Low temperature measurements of pristine graphene by using SQUID magnetometry disclose strong diamagnetism [@snrn10], and show a tiny background paramagnetism, observable at $T<50~K$. The samples under investigation were shown [@snrn10; @nstl12] to consist of electronically decoupled $10-50~nm$ mono- and bilayer graphene crystallites, which are aligned parallel to each other. Evaluation of the spin number $N$ from the measurement data shows that the number of paramagnetic center is proportional to the defect concentration $x$ for a small concentration ($x<0.5$), and the dependence is more complicated for higher concentrations. For each concentration $x$, the measured number of paramagnetic centers is three orders of magnitude less than the measured number of defects in the samples. This experimental fact can be 