Columbia subject headings:
HR diagrams--Congresses.
Solar magnetic fields--Congresses.
Stars--Magnetic fields--Congresses.
Harvard subject headings:
HR diagrams--Congresses.
Solar magnetic fields--Congresses.
Stars--Magnetic fields--Congresses.
Princeton subject headings:
HR diagrams--Congresses.
Solar magnetic fields--Congresses.
Stars--Magnetic fields--Congresses.