SPECIAL WORKS OF REFERENCE 



BARNARD, E. E., On a Great Photographic Nebula in Scorpio, near Antares. 



(Monthly Notices, Royal Astronomical Society, vol. LV, p. 453.) (See also 



Monthly Notices, Royal Astronomical Society, vol. LX, p. 258.) 

 KAPTEYN, J. C., Publications of the Astronomical Laboratory at Groningen. 



(Especially no. 1.) 

 LUDENDORFF, H., Ueber Fehler, die beim Aufcopiren von Normalgittern auf 



photographische Flatten entstehen konnen. (Astronomische Nachrichten, 



no. 3746.) (See also Publ. des Astrophysikalischen Observat. zu Potsdam, Nr. 



49, Bd. xv, Stuck v.) 

 McCLEAN, F., The Spectra of Southern Stars. (See also Monthly Notices, Royal 



Astronomical Society, vol LIX, p. 322.) 

 PERRINE, C. D., The Spectrum of the Nebulosity surrounding Nova Persei. 



(Lick Observatory Bulletin, no. 33.) 

 PICKERING, E. C., A Plan for the Endowment of Astronomical Research, nos. 1 



and 2, Harvard College Observatory. 

 ROBERTS, ISAAC, The Disappearance from Photographic Films of Star-Images 



and their Recovery by the Aid of a Chemical Process (Monthly Notices, Royal 



Astronomical Society, vol. LXI, p. 14.) 

 Report of the Cape of Good Hope Observatory for 1903. (Monthly Notices, Royal 



Astronomical Society, vol. LXIV, p. 307.) 

 For results with Registering Micrometer, Bestimmung der Langendifferenz 



Potsdam-Greenwich im Jahre 1903. (Veroffent. des Konigl. Preussisch. Geodat 



Inst. Berlin, P. Stankiewicz, 1904.) 



