TY  - GEN
AU  - Ferrer Roda,J
TI  - [Difficulties in the classification of tumors]
SN  - 0210-4806
PY  - 1983///0708
KW  - Humans
KW  - Neoplasm Staging
KW  - Neoplasms
KW  - classification
N1  - Publication Type: Editorial
ER  -