898907.fig.0012
Figure 12: A plot of 1723 pulsars from the ATNF pulsar database in the log period-period derivative plane. Nonbinary, nonglobular cluster pulsars are marked by “+” signs, nonglobular binary pulsars by ’s, nonbinary globular cluster pulsars by circles, globular binary pulsars by squares, four strongly magnetized young pulsars by pentagons, and the 2.14 ms signal from SN 1987A by an hourglass.