Christmas boobook lores and throat, yellow eyes, legs and feet. It is approximately 26–29 cm in length and 130-190 grams in weight with the female slightly larger than the male. The double-noted hoot, "boo-book," has a clucking quality with the second note usually lower in pitch. The begging call of juveniles is a high-pitched trill. Vocalisations are similar to those described for the Southern Boobook "N. novaeseelandiae" and include individual variation in advertisement calls. This may be useful in estimating owl densities as radio-tracking can be impractical in some terrains. A recording, courtesy of Richard Hill and Owl Pages http://www.owlpages.com/sounds/Ninox-natalis-2.mp3 Its natural
Refer (software) Refer (software) refer is a program for managing bibliographic references, and citing them in troff documents. It is implemented as a troff preprocessor. refer was written by Mike Lesk at Bell Laboratories in or before 1978, and is now available as part of most Unix-like operating systems. A free reimplementation exists as part of the groff package. , refer sees little use, primarily because troff itself is not used much for longer technical writing that might need software support for reference and citation management. , some reference management software (for instance, RefWorks) will import refer data. refer works with a